A US jury has decided that Dzhokhar Tsarnaev should die for his role in the Boston marathon bombing in April 2013.
Friday's sentence came after 14 hours of deliberations on whether Tsarnaev, who was a teenager when he carried out the attacks with his elder brother Tamerlan, should be imprisoned for the rest of his life or be executed.
The 21-year-old did not react when the sentence was read out.
Tsarnaev was convicted last month of all 30 federal charges against him, 17 of which carried the possibility of the death penalty.
Three people were killed and more than 260 were injured when two pressure-cooker bombs packed with shrapnel exploded near the marathon finish line on April 15, 2013. Dzhokar and Tamerlan also killed a Massachusetts police officer days later.
Boston Police Commissioner William Evans said regardless of how one feels about the death penalty, the verdict was about sending a message that terrorism in the city of Boston will not be tolerated.
