Boston Marathon bombing suspect Dzhokhar Tsarnaev, his face swollen and his arm in a cast, pleaded not guilty to terrorism charges Wednesday in his first courtroom appearance since his dramatic capture in April.

Tsarnaev, 19, smiled crookedly — he appeared to have a jaw injury — at his sisters as he arrived in court. He looked much as he did in a photo widely circulated after his arrest, his hair curly and unkempt. He appeared nonchalant, almost bored.

He leaned toward a microphone and said, "Not guilty" in a Russian accent to 30 federal charges, including using a weapon of mass destruction to kill. He made a kissing motion toward his family as he was led out of the courtroom.

He could get the death penalty if prosecutors choose to pursue it.

The April 15 attack with a pair of pressure-cooker bombs near the finish line of the country's most well-known marathon killed three people and wounded more than 260. Authorities say Tsarnaev orchestrated the attack along with his older brother, Tamerlan Tsarnaev, who died following a shootout with police three days after the bombing. Authorities say the brothers of ethnic Chechen descent killed a police officer while they were on the run.

Dzhokhar Tsarnaev was arrested on April 19 when he was found hiding in a boat in a suburban backyard. He was initially charged in a hospital where he was recovering from wounds suffered in a police shootout.

Prosecutors say Tsarnaev, a Muslim, wrote about his motivations for the bombing on the walls inside the boat where he was captured. He wrote the U.S. government was "killing our innocent civilians."

Tsarnaev's two sisters were in court Wednesday. One of them sobbed. His parents remained in Russia.

About a dozen Tsarnaev supporters cheered as his motorcade arrived, yelling, "Justice for Jahar!" as Tsarnaev is known. One woman held a sign that said, "Free Jahar."

Lacey Buckley, 23, said she has never met Tsarnaev but came because she believes he's innocent. "I just think so many of his rights were violated. They almost murdered an unarmed kid in a boat," she said.

A group of Tsarnaev's friends waited in line outside the courtroom for hours, hoping to get a seat.

"Just knowing him, it's hard for me to face the fact that he did it," said Hank Alvarez, 19, who called his friend calm, peaceful and apolitical.

"There was nothing sketchy about him," said another friend, 20-year-old Shun Tsou, who added that he had not formed an opinion on Tsarnaev's guilt or innocence.