1am ET Gunfire and explosions are heard in Watertown. The suspects throw explosives and exchange gunfire with police. One suspect is wounded, and a policeman is seriously injured. The other suspect escapes capture. The wounded suspect is taken to Beth Israel Deaconess medical centre where he dies from "multiple traumatic injuries" . Public transport is shut down and residents of several neighbourhoods are told to stay inside and not open their doors.
8.20am ET Police suspend the city's taxi service and warn all residents of Boston to stay at home.
8.30am ET Police formally identify the suspects as brothers Tamerlan Tsarnaev, 26 (Suspect One), who died in hospital, and Dzhokhar Tsarnev, 19 (Suspect Two), who remains at large.
8.45am ET Police arrive at a house in Watertown where police use loudspeakers to urge someone inside to come out. It appears to be a false alarm.
11.04am ET @FBIBoston tweets: "Bombing suspect may be driving 4-door, '99, green Honda Civic w/ Mass. plates reading: 116GC7."
12.17pm ET @FBIBoston says it is no longer seeking the Honda Civic.
6.15pm ET The Massachusetts governor, Deval Patrick, announces the resumption of public transport and says residents may leave their homes. Police say the bombing suspects do not appear to have been involved in the armed robbery at the grocery shopon Thursday night.
7.05pm ET Gunshots are heard in Watertown. Police again ask residents to stay inside.
8.45pm ET The manhunt is brought to an end when Boston police announce they have caught Dzhokhar Tsarnaev. He is located after a resident notices a trail of blood leading to his boat parked by his house.