This is a special edition of nightline. Inside the pulse nightclub terror. Good evening and we are dedicating our entire show tonight to the wrenching new body cam video from the officers who responded to the massacre at the pulse nightclub in orlando. It was nearly a year ago america witnessed its deadliest mass shooting. Tonight you will watch as those officers storm into that club not knowing what they would find on the other side. Heres abcs chief investigative correspondent brian ross. Hatnds up this way just go, just go, just go reporter 11 hours of new videos made public today. Show the chaos and carnage of that horrible night. I see shadows moving in there. Reporter as Police First Responders try to save the wounded and hunt down the killer. Police reporter next week marks one year since the attack. And the images, memories and emotions in orlando are still raw. The look in their eyes, see that they had seen something they had never, ever seen before. Reporter that weekend would begin in tragedy on friday night and would only get worse. This is joe on a recorded line. Somebody just opened fire at the plaza live. Our officers responded to a nightclub shooting where Christine Grimmie was shot and killed. Reporter 24 hours later another killer was waiting. Driving to orlando from his home two hours away. Heading into the city on interstate 4. Heavily armed. The target, the pulse nightclub. A popular spot in the citys gay community. Inside, it was latin night. Our regulars were out having a good time. We were all like in a great mood. We were in the club dancing. One or two minutes after alcohol was done, all of a sudden there was a shot. Shots fired, shots fired reporter an offduty Police Detective working security at pulse, adam grueler, radioed in. Shots fired, 1912, south orange avenue, multiple down, signal 43 what does that mean . Emergency assistance, we needed you five minutes ago. Reporter less than 90 seconds after signal 43 goes out, backup units begin to arrive. Including one officer from the bicycle patrol downtown. Graham cage. I heard the emergency call. And i just jumped on my bike and was quick as possible. Reporter this newly released video comes from the body cam worn by officer cage as he arrived at the nightclub. Thats where they are. I see shadows moving in here. You ran in there where there was an active shooter. You dont have heavy body armor. What youre see me wearing right now, light vest, thats it. Look behind you. What do you know . Police emergency, natasha. Your calls record. Please tell the cops to come. Did you see the shooter inside the club . No, but theyre talking. What are they saying . Can you make out the words . No, please, theyre going to kill us. Right when we were about to go in, we were still hearing shots. It opens up. Behind the fence it opens up. Show us your hands is there anybody else in here . No i called 911 show us your hands. I got his hands, come out. Come out, come out. Were policemen, come out. Hurry up, hurry up, hurry up. Come out hands up, hands up. Hands up, coming out. What are we doing now . Getting more, just trying to get them out. Reporter the bullets missed jackie but hit the two friends she was standing with. One mortally. Gunshot wound to his chest. I saw that he was injured. He was nonresponsive. Reporter bodies, dead and wounded everywhere. Those images are blacked out by police as required by florida law. Those first few officers that get there need to go to that scene, go to the building, and get in and engage that shooter. Chase after the shooter . Thats correct. Reporter Police Training calls for officers to head straight to the active shooter. Even fit means going past the victims. Plenty more victims in here. A person reached up. And asked for help. But at that point we didnt know where the shooter was, if he was detained, if he was deceased, or what was going on. So as much as i wanted to help him, i could not help him until we knew for sure. You had to walk away from the vict victim . Yes. This is going to be astronomical numbers. We continue down the southeast side. Stepping over bodies. Then as i looked to my right, i see two of our officers start shooting down a hallway. Suspected barricaded inside with multiple hostages, multiple people down and shot. They saw him, saw a threat, gamed that threat. What happened to the shooter . He holed up inside a bathroom inside the business. We have him contained in the bathroom. Reporter the orlando s. W. A. T. Team is in place led by major mark canty. Just kind of went quick from active shooter to barricaded gunman, hostage situation. Did you decide to just go in and get him if. No. Reporter it was a decision later criticized by some, as it would take three hours for police to gain full control and get all the wounded back to safety. Chief john mena in the command post says it was the right call. We were in there saving people from the dance floor, from dressing rooms, from the other bathroom. And in fact we took 22 people out of the front bathroom. Once we were inside that club, there were no more gunshots until the final assault. Reporter but the shooter was still inside, cornered and dangerous. Emergency 911, this is being recorded. In the name of gracious god what . The merciful god i want to let you know im in orlando and i did the shooting. Reporter a half hour after he first hoped fire the shooter called into the Orlando Police department dispatch center. Okay. Whats your name . I pledge my allegiance to Abu Bakr Al Baghdadi on behalf of the Islamic State. She asked him to repeat what he was saying. Whats your name . I pledge my allegiance to Abu Bakr Al Baghdadi on behalf of the Islamic State. The dispatcher said, you need to hear this call. Reporter Sergeant Andy brennan, trained Hostage Negotiator, was working an offduty detail at a bar downtown that night. When he responded to the signal 43 call at pulse. And headed to the dispatch center. So i went and sure enough, five minutes later, this shooter calls in. Where are you at . In orlando. Where in orlando . Reporter the shooter hung up, as he would again and again that night. Chilling. I said, lets call. So we made our first call. Immediately. From that dispatchers station. Hello there. Hi, there. This is Orlando Police, who am i speaking with, please . Youre speaking with the person who pledges allegiance to the Islamic State of Abu Bakr Al Baghdadi we wanted to confirm we had in fact the person that was inside. You can start to hear the serious tone in his voice. Reporter for the next 55 minutes, brennan will engage the shooter on the phone, listening to his rants about isis and syria. They need to stop the u. S. Air strikes. You have to tell the u. S. Government to stop bombing. I understand that. But heres why im here right now. Im with the Orlando Police. Can you tell me what you know about whats going on tonight . Whats going on is that i feel the pain of the people getting killed in syria and iraq. Okay. So have you done something about that . Yes, i have. Tell me what you did, please. You already know what i did. Reporter at the scene, officers are using the time to get as many victims out as possible. Were trying to get people who are breathing out of here. Hands up, hands up reporter one big concern the shooter might try to hide among the places youd think only t people could hide we were finding ten people. Reporter officer james hyland arrived in his personal pickup truck which was turned into a makeshift ambulance by his partner. We didnt have any ambulances or anything there. He started loading people up. He just jumped in the truck. I left it unlocked. He was going back and forth doing one run after another after another. Reporter others could not be reached and they used their phones to call loved ones who called 911 and pleaded for help. My girlfriends in the bathroom. There are now four dead in the bathroom and two shot and bleeding out. If somebody be doesnt get there soon theyre going to die. My son is shot in the club in the pulse in oral. Hes still in the bathroom where hes bleeding. He got shot and nobodys going in for him. Reporter by pressing the phone number negotiator brennan had learned the shooters name, omar mateen, a 29yearold son of afghan immigrants, an angry and troubled man with a history of violence and failure. Omar, this is andy from Orlando Police. At some point you start to call him omar. Yes. If you introduce a level of familiarity, theres less opportunity that this person is going to be depersonalized. Reporter but then the negotiator hears words from mateen that quickly change the dynamic for everyone inside the nightclub. By the way, theres some vehicles outside that have some bombs, just to let you know. Your people are going to get it. Im going to innight fit they try to do anything stupid. Okay, i understand that. Ill pass that along. Can you tell me what vehicles . I dont want to see anybody get hurt. No. But ill tell you this. It can take out a whole city block almost. Reporter a frantic search begins for the shooters car. Once more the threat escalates. I have a vest. Okay, you have a vest. I understand that. Okay, so what kind of vest are you talking about . Is it a bulletresistant vest . Is it a bomb vest . No. Its what they used in france. Its what they used in france. I got to go. Were getting a report that somebody in one of the bathrooms may have an explosive device wrap strapped to him. In the building. You may not want to stay there. Reporter but not a single officer pulled back to safety. In it to win it. You werent going to leave . No. Reporter the police prepare to move in when we return. Keep coming right behind you. Out . Including this little girl. And what if this happened again . I was given warfarin in the hospital, but wondered, was this the best treatment for me . So i asked my doctor. And he recommended eliquis. Eliquis treats dvt and pe blood clots and reduces the risk of them happening again. Yes, eliquis treats dvt and pe blood clots. Eliquis also had significantly less major bleeding than the standard treatment. Both made me turn around my thinking. Dont stop eliquis unless your doctor tells you to. Eliquis can cause serious and in rare cases fatal bleeding. Dont take eliquis if you have an artificial heart valve or abnormal bleeding. If you had a spinal injection while on eliquis call your doctor right away if you have tingling, numbness, or muscle weakness. While taking eliquis, you may bruise more easily. And it may take longer than usual for bleeding to stop. Seek immediate medical care for sudden signs of bleeding, like unusual bruising. Eliquis may increase your bleeding risk if you take certain medicines. Tell your doctor about all planned medical or dental procedures. Eliquis treats dvt and pe blood clots. Plus had less major bleeding. Both made eliquis the right treatment for me. Ask your doctor if switching to eliquis is right for you. We all drive, some cats just know how to roll. Beneful grain free is so healthy. Oh farmraised chicken thats good chicken. Hm . Here come the accents. Blueberries and pumpkin. Wow. And spinach that was my favorite bite so far. avo new beneful grain free. Out with the grain, in with the farmraised chicken. Healthful. Flavorful. Beneful. To take advantage of this offer on a volvo s90, visit your local dealer. This special edition of nightline continues. Reporter with victims still trapped inside and the threat of massive explosives, Orlando PoliceHostage Negotiator andy brennan knew he was running out of time. Tell me whats going on right now, omar. Whats going on is that the air strikes need to stop. Ive heard that and i want you to come outside and tell us that yourself. So the message rings true from you. Not me passing along your message. Im doing that. But i need you to come outside with no weapons. Omar. Yep, he did hang up, 3 25. Reporter that was the fourth and final call between brennan and the shooter. The chief decides his officers will have to storm the back bathrooms of the nightclub. I wasnt going to sit here in this command post knowing he was going to blow up everyone, all those hostages, inside that club. There were many hostages left inside. It was your decision alone . It was my decision alone. Reporter the s. W. A. T. Team outside knows where the hostages are hiding. And they help them push a window air conditioner out of the way to create an escape opening. Theres someone knocking on the window, someones knocking on the window. Someones knocking on their window. Is it the air conditioning window . Yep. Theyre knocking it in. Thats us, maam. Were going to push the air conditioning unit in. Before we do, you guys have to catch it because if you let it drop or you make any noise, the killers going to know where youre at and he might shoot through the walls and kill you. Did they catch it . You see all their hands reach up and grabbed it, able to lower it to the ground without making a sound. I think the first person that came out was the person that was injured. They were able to get out by themselves. Reporter eight hostages ran for their freedom. Hey, over here, lets go, over here in the parking lot reporter elsewhere outside pulse, jackie made her escape, carrying her friend shot in the chest, who would later die. Waiting outside was her father, an orlando firefighter. I give her a quick onceover. Make sure she has all her body parts and shes okay. Because i know that she could have been one of those who were killed or injured. It wasnt until he was there and i knew that i could kind of collapse in his arms and id be okay. Reporter using an armored vehicle, a bearcat, to bust open holes in the wall and create an escape route, driven by officer rob woodger. You could see them coming out . Oh, yes. Every person we got out was a victory for us. At that point we need to get these people out of this building. One by one theyre coming out of holes and its a great feeling seeing them come out. This way, this way lets go, just go, just go move back to a safe location, please, get away from the sidewalk. When theyre running for their life, they had no idea what was going on. They were thing in the bathroom, chaotic. Was there concern by doing the breach, going through the wall, the gunman might open up on the other hostages . Yes. There was a concern. But youre trying to save as many people as you can. So i mean, theres 13 people in that bathroom. You want to save them. Theres five with him. It was a risky call, wasnt it . Yeah, yeah. Reporter but it worked. And drew mateen, the shooter, out into the open, firing at the officers and the bearcat. Like a wall of shooting. 30 seconds of the most awesome sound you could hear. Because it was us returning fire towards him. And then one of the bullets struck officer napolitano right in the kevlar helmet. Probably within an inch of losing his life. Hold on, brother, i got you, i got you. He went down to the ground. Still returning fire. And the other officers there returned fire, killing the suspect. If that shot had been an inch lower . He would have been dead, no doubt in my mind. Your guys so lucky. Got hit in the helmet . [ bleep ] right between the eyes. Really . Right here, dude. Reporter then the radio call. Suspect down. And a giant cheer went up in the comm center and i was right there with them. Reporter the worst mass shooting in American History had ended. What do you still see in your head when you think about what you saw that night . The sound of cell phones ringing. Looking down, i could see phones laying i mean, multiple phones just laying in pools of blood. Knowing that thats somebodys loved one trying to get ahold of their loved one. And theyre not able to pick up that phone. Oh, it was 20, 30 phones constantly going. I mean, one starts, another stops. Three of them going over there. It was constant. That was hours. People trying to reach loved ones. Yes. Must have been so sad. It was. I think that was probably actually the most eerie thing. Reporter and soon the horror of it all took hold. Several of us commented that this is going to change the city forever. Probably change what we do forever. Reporter for nightline, brian ross, abc news, orlando. Our thanks to brian ross for his extraordinary reporting tonight. And well be right back. You might not ever just stand there, looking at it. You may never even sit in the back seat. Yeah, but maybe you should. laughter but youve never had em quite like this. At red lobsters lobster shrimp summerfest, the lobster and shrimp you love are teaming up in so many new ways. Like new coastal lobster and shrimp, with a lobster tail with butter and herbs, sweet, smoky bbq red shrimp, and shrimp crusted with. Get this. Cape cod kettle chips. Or try lobster and shrimp overboard. A dish this good. Makes you this hungry. Its the highlight of the season, and cant last. So hurry in. Studying to be a dentist and she gave me advice. She said. My daughter is. Dadgo pro with crest prohealth. 4 out of 5 dentists confirm. These crest prohealth. 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Com for a store near you. We have one final note here tonight. Its a sad one. We learned that after surviving the pulse attack last year, Jackie Seville was tragically killed this past memorial day weekend in a traffic accident. Our thoughts are with her family and with everybody affected by the pulse shooting. We want to thank you for watching abc news tonight. As always were online 24 7 at abcnews. Com and our Nightline Facebook page. Thanks again for watching and good night