Boston Marathon bomber trial: Dzhokhar Tsarnaev is a "terrorist" who should be sentenced to death, prosecutors tell jury

Comment made as prosecution concluded its case

Dzhokhar Tsarnaev had denied the multiple charges he faced

Boston Marathon bomber Dzhokhar Tsarnaev is a “terrorist” who wanted to punish America and should be put to death, a jury was told on Tuesday as prosecutors closed their case against the 21-year-old.

The federal prosecutor heading the case against Tsarnaev, Steven Mellin, said it was clear that the troubled young man had turned against the country that had adopted him.

He said that four days after the 2013 – at a time when he was injured and still hiding from police – Tsarnaev had written: “Now I don't like killing innocent people, but in this case it is allowed because America needs to be punished.”

Sister Helen Prejean (Reuters)

Mr Mellin told the jury: “These are the words of a terrorist who is convinced he did the right thing.”

Tsarnaev was found guilty of all 30 charges on April and faces either the death penalty or else life without the prospect of parole.

The case has been painful for the city of Boston, where three people were killed and more than 260 injured after Tsarnaev and his brother set off homemade explosives close to the finish line.

It has also forced an examination of public views on the death penalty. Massachusetts does not carry the death penalty on its statues – Tsarnaev is being prosecuted by the federal government – and many have called for his life to be spared.

Martin Richard was one of three people killed in the 2013 attack

Among those who have said they would prefer him to be sentenced to life in jail are the parents of eight-year-old Martin Richard, one of those who lost their lives.

Mr Mellin showed the jury photos of the bombing's immediate aftermath, with victims whose legs were blown off sitting in pools of blood, the Associated Press said. He also showed a second image of a 29-year-old restaurant manager screaming in pain before she died of her injuries.

The defence have said Tsarnaev was under the overbearing influence of his elder brother, Tamerlan. who was killed in a shout-out with police, days after the attack.

As part of their care, the defence called as a witness Sister Helen Prejean. The activist , whose memoir Dead Man Walking was turned into a film, said she had met Tsarnaev and that he had spoken of his regret.

The same jury that found Tsarnaev guilty must now decide whether he lives or dies.