Boston Marathon Bomb Suspect Reportedly ‘Cocky, Nonchalant’ While Pleading Not Guilty

Reports: 'Yawning,' distracted Tsarnaev makes his first public appearance

Dzohkhar Tsarnaev, the surviving brother accused of plotting the Boston marathon bombings that killed three people and wounded over 260, reportedly appeared to cop an attitude as he pleaded not guilty Wednesday to all 30 charges in a Boston federal courtroom.

It was his first public appearance since his April 19 arrest in a Watertown man's backyard; he's also accused of killing an MIT police officer during the subsequent manhunt.

Tsarnaev's brother, Tamerlan, was killed during an April 18 confrontation with police.

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Tsarnaev, described as "yawning, eyes wandering around the room, rubbing face while judge speaks" by Boston Globe reporter Eric Moskowitz and "nonchalant, almost cocky as he strutted into the room" by Globe's David Abel spoke into a microphone during the seven-minute-long arraignment to say "not guilty" when ordered by the judge. He wore an orange prison jumpsuit and a cast on his left hand.

In the court were several victims of the bombings, all of whom declined to speak when the judge offered them a chance. There were also, according to the Boston Globe, about a dozen Tsarnaev supporters.

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The 19-year-old could face the death penalty if convicted of his crimes, though it is still not known if federal prosecutors will pursue it. He will return to the courtroom on Sept 23.

Plans are already in the works to make a film based on the Boston Marathon Bombings.