The jury in Massachusetts will now decide what sentence 21-year-old Dzhokhar Tsarnaev will receive.

Three people were killed and more than 260 injured when the bombs exploded at the finish line in April 2013.

His lawyers admitted he played a role in the attacks but said his older brother was the driving force.

The guilty conviction was widely expected. In the next phase of the trial, Tsarnaev's legal team will push for him to be given a life-in-prison sentence instead of death.

His chief lawyer, Judy Clarke, specialises in defending high-profile clients facing the death penalty, including the Unabomber, Ted Kaczynski.

Although Tsarnaev's defence team had repeatedly appealed for a change of venue, Boston is not known for its support of capital punishment.

Massachusetts abolished the practice in 1984 and has not executed anyone since 1947. But Tsarnaev was convicted of federal, not state crimes.

A police officer was killed in the days following the attack as Tsarnaev and his brother, who also died, attempted to flee.

As the guilty verdicts were read on Wednesday, Tsarnaev kept his hands folded in front of him and looked down.

Nearby, the mother of one victim, eight-year-old Martin Richard, wiped tears from her face after the verdict was read. Richard's father embraced one of the prosecutors.

The governor of Massachusetts welcomed the verdict, and Boston Mayor Martin Walsh said: "I hope today's verdict provides a small amount of closure".

The family of Officer Sean Collier, who was killed days after the attack, said: "While today's verdict can never bring Sean back, we are thankful that Dzhokhar Tsarnaev will be held accountable for the evil that he brought to so many families."

Tsarnaev's defence team say he took part in the bombing, but argue that his elder brother, Tamerlan, was the mastermind of the attack who influenced Tsarnaev into participating.

Prosecutors portrayed the brothers as equal partners in a plan to "punish America" for wars in Muslim countries.

Among the most damning evidence was a video that showed Tsarnaev placing a backpack bomb near to Martin Richard, and a statement scrawled inside the boat where he was found hiding days after the attack.