Tsarnaev, 19, smiled crookedly — he appeared to have a jaw injury — at his sisters in court as he arrived.
Then, after he leaned over toward a microphone and said, “Not guilty” over and over in a Russian accent, he was led out of the courtroom, making a kissing motion toward his family as he left.
The proceedings lasted just seven minutes and took place in a courtroom packed with victims of the bombing, their families, police officers, and members of the public and the media.
Tsarnaev faces 30 charges, including using a weapon of mass destruction to kill.
Tsarnaev, who could face the death penalty, appeared in court for the first time since he was found hiding in a boat in a suburb days after the April 15 explosion.
The 30-count indictment against Tsarnaev includes 17 charges carrying the death penalty or life imprisonment. Aside from bombing-related counts, it also contains charges covering the slaying of a police officer and the carjacking of a motorist during the getaway attempt that left Tsarnaev’s older brother, Tamerlan, dead.
The courthouse was jammed with media, supporters, ex-classmates and victims’ families. Tsarnaev’s two sisters, both dressed in Muslim garb, were there. One was carrying a baby, the other wiped away tears with a tissue.
Reporters and spectators began lining up for seats in the courtroom at 7.30am as a dozen Federal Protective Service officers and bomb-sniffing dogs surrounded the courthouse.
Four hours before the hearing, the 19-year-old arrived at the courthouse in a four-vehicle motorcade that included a van, a Humvee and a state police car.
A group of about a dozen Tsarnaev supporters cheered as the motorcade arrived. The demonstrators yelled “Justice for Jahar”, as Tsarnaev is known. One woman held a sign that said, “Free Jahar”.
A group of friends who were on the high school wrestling team with Tsarnaev at Cambridge Rindge and Latin waited in line outside the courtroom for hours, hoping to get a seat.
Tsarnaev’s initial court appearance took place at a hospital, where he was recovering from injuries suffered in a shootout with police the day before in the Boston suburb of Watertown.
Authorities say he had escaped in a hijacked car after running over his brother and alleged co-conspirator, Tamerlan Tsarnaev, who died following the shoot-out with police.