seriously his daughter is injured. >> so i ask him in no uncertain terms, i needed to know just myself, what's your opinion, how bad was this? and he said this was a mortal wound. and if the people did not get to her when they did, she would have bled to death. >> those people saved her life. >> i'll never forget those words. >> reporter: matt smith who helped save sydney's life, visits her in the hospital. >> i spoke with him first and thanked him. we both cried together. you couldn't meet a nicer guy. i just got so lucky that these people were actually in the area and did what they did. >> reporter: just before 9:00 p.m., officials confirm three deaths from the bombings. 23-year-old boston university grad student lingzi lu. a boy, 8-year-old martin richard and a 29-year-old named krystle