Cllr Colin Brotherton, the Mayor of Boston in Lincolnshire, has sent a letter of condolence to. his counterpart in Boston, Massachusetts. The two communities are twinned and share strong bonds.
A number of memorial stones are in place outside Boston Stump to commemorate those who travelled from the town to Boston MA. A candle has also been lit inside the church itself as a mark of respect.
Councillor Colin Brotherton Mayor of Boston has written to the Mayor of Boston MA to express his condolences.
A runner's camera captured the first explosion at the finishing line of the Boston Marathon. Three people were killed and more than 100 injured as two blasts sent smoke and debris soaring into the air.
Former Metropolitan Police Officer Graham Whettone has told Daybreak that security protocols surrounding Margaret Thatcher's funeral will most likely be reviewed in light of what happened at the Boston Marathon.
He said: "If they need to advance [the plans] then they will do, there's different tactical options the police can employ at various events, they will just review those now, if they need to advancer them then they will do."
The total of people injured by blasts at the Boston Marathon has risen to 144 people, officials at Boston area hospitals said to CNN.
At least three people were killed by two blasts at the finish line of the Boston Marathon, police confirmed.
Doctors said that many of the injured who were admitted to hospital had severe leg injuries caused by shrapnel, and confirmed at least 10 amputations.
Amateur video shot by a spectator showed the aftermath of the first detonation shortly before a loud bank signals the second bomb going off.
The footage shows a mushroom of smoke billowing up between buildings as crowds of onlookers scramble to leave the viewing stands.
Cries of "get out of the stands" can be heard along with sirens and screams.
Warning: This footage contains scenes which may cause distress.
Boston Police Commissioner Edward Davis has told reporters there were three separate explosions in Boston - the first two near the finish line of the marathon and a third at the John F. Kennedy Library in the city.
He said that police were treating the explosions as related.
Here is an excerpt from the briefing he just gave to reporters:
The JFK Library in Boston has tweeted to say that there was fire in the building which has now been extinguished and that it is "pure speculation" to link it with the Boston Marathon explosions:
Fire in building is out, appears to have started in the mechanical room of new building. All staff and visitors are accounted for and safe.
Investigators are investigating. Any tie to Boston Marathon explosions is pure speculation. More information as we receive it.