homemade explosives in watertown. >> we are asking the public to remain vigilant. >> reporter: 6:00 p.m., the lockdown is lifted. people can leave their homes. and less than an hour after the lockdown is lifted, shots are fired and police go to the scene. >> reporter: i just heard what sounded like multiple assault rifle shots. >> reporter: and then cornered on a boat in watertown. hundreds of agents surround the suspected bomber, and many around boston break out in tears, followed by the crowd coming to the streets to celebrate. >> now is one of the brief glimpses we got on friday night of the suspected bomber. and this was tweeted by one