A jury yesterday found Dzokhar Tsarnaev guilty of killing three people and injuring 264 in the 2013 Boston Marathon bombing, as well as fatally shooting a police officer four days later.

Tsarnaev, 21, was found guilty of all 30 counts against him, with 17 of the charges carrying the death penalty. The same US District Court jury will now decide whether to sentence him to death or life in prison without possibility of parole.

Tsarnaev silently looked down, occasionally fidgeting, as the lengthy verdict was read. The courtroom was packed with survivors of the attack, the parents of eight-year-old Martin Richard, the youngest fatality, and law enforcement officials, including former Boston Police Commissioner Ed Davis.

Jurors spent just over 11 hours evaluating Tsarnaev’s guilt in two days of deliberations, following 16 days of testimony.

Defence lawyers began the trial by admitting that Tsarnaev carried out the April 15, 2013, bombing but said he did so at the bidding of his older brother Tamerlan, 26, who died following a gunfight with police in Watertown, Massachusetts.

Prosecutors laid out evidence that the defendant, an ethnic Chechen who immigrated from Russia a decade before the attack, had read and listened to jihadist materials, and wrote a note in the boat where he was found hiding suggesting the bombing was an act of retribution for US military campaigns in Muslim-dominated countries.

The blasts killed restaurant manager Krystle Campbell, 29, Chinese exchange student Lingzi Lu, 23, and Richard. Tsarnaev also was found guilty of the fatal shooting of Massachusetts of Institute of Technology police officer Sean Collier, 26.

Federal prosecutors detailed jihadi writings, including a copy of al-Qaeda’s Inspire magazine with an article on bomb-making found on of Tsarnaev’s computers, describing that as evidence that he was an extremist who wanted to “punish America.”