Convicted Boston Marathon bomber Dzhokhar Tsarnaev was sentenced to death Friday after a Boston jury's third day of deliberations.



Tsarnaev showed little expression as he heard the sentence, and the courtroom was solemn throughout the proceedings.

The 21-year-old was convicted last month of killing three people and injuring 264 others by detonating homemade bombs at the Boston Marathon finish line on April 15, 2013. Three days later, he and his 26-year-old brother shot a police officer to death, carjacked a Chinese businessman and hurled bombs at police, triggering a day-long lockdown of most of the Boston area as police searched for Tsarnaev.

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Tsarnaev will remain in custody, with a formal sentencing in the coming months. He will become the youngest person on federal death row.



An appeals process could take years before Tsarnaev is killed by lethal injection.