New Footage Shows Boston Bomber's Reaction As Bombs Go Off

The court that will decide the fate of Boston bomber Dzhokhar Tsarnaev has been shown video of the terrorist leaving a crowded area just before his weapon explodes.

Surveillance footage compiled by the FBI features Tsarnaev, 19 at the time, standing alongside spectators of the Boston Marathon as he awaits the detonation of the bomb set by his older and deceased brother, Tamerlan Tsarnaev.

It was here he planted his own bomb, Daily Mail reports, which was said to have been made with a pressure cooker and concealed in a garbage can.

The first bomb goes off away from the crowd in frame at about 7:43.

Everyone looks to the left with concern but Dzhokhar starts walking past the concerned spectators to the right.

His bomb goes off right where he was standing about 12 seconds later.

Dzhokhar is then seen fleeing the scene without the backpack he was carrying moments before, and it appears he pushes some people out of his way to get ahead.

Warning: The following footage shows a brief moment of the second bomb exploding at 7:55.

The two blasts killed three people and injured more than 260 on April 15, 2013.

Tamerlan, 26, was killed during a shootout with police on April 19.

Dzhokhar was found hiding in a boat in the backyard of a house in Watertown, MA that same night.

Federal prosecutors are seeking the death penalty for the surviving brother.

His defense team is claiming that Tamerlan Tsarnaev was the sole mastermind behind the attack and had convinced his younger brother to participate.

Dzhokhar Tsarnaev had written on the boat he was found in that the bombings were triggered by America's intervention in the Middle East and he was seeking revenge for the slaughter of Muslims.

Citations: Boston bomber pushed his victims out of the way as he fled (Daily Mail)