(USA TODAY) -- Boston Marathon bombing suspect Dzhokhar Tsarnaev pleaded not guilty Wednesday to 30 counts of using a weapon of mass destruction stemming from the Boston Marathon bombing.
He entered the plea in federal court in Boston where he was facing arraignment.
He said "Not guilty" in a Russian accent and repeated his plea for the court multiple times.
The arraignment marks his first public appearance since he was arrested April 19.
Hours before the hearing, Tsarnaev arrived at the federal courthouse in a four-vehicle motorcade that included a van, a Humvee and a state police car.
Several of the charges could bring the death penalty for Tsarnaev, 19, accused in the April 15 blasts that killed three people and wounded more than 200. Tsarnaev also is accused of killing an MIT police officer.
His brother, Tamerlan Tsarnaev, was killed in a shootout with police following a massive manhunt three days after the bombings. Dzhokhar Tsarnaev was captured the next day -- wounded and bloodied from the shootout -- after a Watertown homeowner noticed blood on his dry-docked boat. Police found the suspect hiding inside.
This marks the suspect's first public appearance since his arrest. A spokeswoman for the U.S. attorney's office said space is being reserved in the main courtroom for victims' families, but she wouldn't indicate how many planned to attend. Court officials have set aside an overflow courtroom to broadcast the hearing for the news media.
Authorities say the brothers were inspired by al-Qaeda publications and that Dzhokhar Tsarnaev left a confession in the boat justifying the bombings as payback for U.S. military action in Muslim countries.
He wrote the U.S. government was "killing our innocent civilians."
"I don't like killing innocent people," he said, but also wrote: "I can't stand to see such evil go unpunished. ... We Muslims are one body, you hurt one you hurt us all."
Tsarnaev's arrest stunned those who knew him as a likable high school athlete in Cambridge, Mass., where he lived with his older brother after his parents left for Russia.
The indictment also said that, sometime before the bombings, Tsarnaev downloaded Internet material from Islamic extremists that advocated violence against the perceived enemies of Islam.
Three people - Martin Richard, 8, Krystle Marie Campbell, 29, and Lingzi Lu, 23 - were killed by the bombs, which were improvised from pressure cookers. Authorities say the Tsarnaevs also killed Massachusetts Institute of Technology officer Sean Collier days later while they were on the run.
Contributing: William M. Welch, USA TODAY: Associated Press