Dzhokhar Tsarnaev, the 19-year-old suspect in last week's Boston Marathon bombings, has been charged with carjacking and "using a weapon of mass destruction," and could face the death penalty.

Tsarnaev, lying in a hospital bed and recovering from wounds—some possibly self-inflicted—sustained during and after a firefight with police on Thursday night, was arraigned by a federal agent this afternoon, and the criminal complaint quickly unsealed. Signed by Special Agent Daniel Genck, the complaint (embedded below) recounts in detail the evidence from nearby security cameras:

The Forum Restaurant video shows that Bomber Two remained in the same spot for approximately four minutes, occasionally looking at his cell phone and once appearing to take a picture with it. At some point he appears to look at his phone, which is held at approximately waist level, and may be manipulating the phone. Approximately 30 seconds before the first explosion, he lifts his phone to his ear as ifhe is speaking on his cell phone, and keeps it there for approximately 18 seconds. A few seconds after he finishes the call, the large crowd of people around him can be seen reacting to the first explosion. Virtually every head turns to the east (towards the finish line) and stares in that direction in apparent bewilderment and alarm. Bomber Two, virtually alone among the individuals in front of the restaurant, appears calm. He glances to the east and then calmly but rapidly begins moving to the west, away from the direction of the finish line. He walks away without his knapsack, having left it on the ground where he had been standing. Approximately 10 seconds later, an explosion occurs in the location where Bomber Two had placed his knapsack.

The charges mean Tsarnaev could face the death penalty if convicted.