Boston Marathon bomber Dzhokhar Tsarnaev broke his silence Wednesday at his formal death sentencing, asking, "Allah to bestow mercy upon those I killed and their families." 

"I am guilty of the bombing, let there be no lingering question about that," said Tsarnaev. "After the bombing, I learned the victims' names and saw their faces. I also wish more people had the chance to testify. But I took them from you. I am sorry for the lives that I've taken, the sorrow I have caused. I have done irreparable damage."

It was the first time the convicted terrorist, 21, had publicly spoken since his April 2013 arrest, save for his July 2013 arraignment in which he verbally pleaded "not guilty."

“I am sorry for the lives I have taken, for the suffering I have caused and for the terrible damage I have done,” said Tsarnaev.

Tsarnaev fidgeted, scratched his head, cracked his knuckles and infrequently stared at the speakers in federal court where he was formally sentenced to death for his part in the deadly terror attack, but not before he faced the people whose lives he forever changed.

The floor was open for three hours of victim impact statements, strained if not teary accounts included descriptions of brain injuries, hearing loss, shrapnel wounds, amputated limbs, headaches, nightmares, PTSD, surgeries, out-of-pocket payments and unbroken spirits.

Tsarnaev was found guilty in April of carrying out the deadly terror attack, which killed three and injured 264 others; 17 people lost limbs. His late brother, Tamerlan Tsarnaev, was the alleged mastermind of the plot, which they carried out on April 15, 2013. Days later, the men shot dead MIT police officer Sean Collier in an attempt to flee the city. 

"I ask Allah to have mercy upon everyone here today, on me and my brother," Tsarnaev said Wednesday.

Tsarnaev will receive lethal injection in Indiana’s Terre Haute State Prison, the same facility where Oklahoma City Bomber Timothy McVeigh was put to death.

Judge Gregory O’Toole told Tsarnaev he followed a “cruel god,” not the God of Islam, if he thought God wanted him to kill innocent people.

“No one will remember that your teachers were fond of you, that you were funny, a good athlete,’’ O’Toole said. “Whenever your name is mentioned, what will be remembered is the evil you have done. What will be remembered is that you murdered and maimed. You had to forget your own humanity.”

The parents of Martin Richard, 8, who died as a result of his injuries after Tsarnaev placed his bomb directly behind Richard, spoke of choosing love over hate in the face of the violence their family suffered.

“He chose hate. He chose destruction. He chose death,’’ Richard said. “We choose love. We choose kindness. We choose peace. This is our response to hate. That’s what makes us different from him. We wanted him to have a lifetime to reconcile, but he will have less than that.”

Legal experts told Metro Tuesday that Tsarnaev would likely not speak, and that if he did, it would not help his appeal. 

MBTA Transit Police officer Richard "Dic" Donohue also took the stand, calling his friend Sean Collier "special."

“Through out my recovery, the most gut-wrenching time was when I had to watch my friend Sean’s funeral from my hospital bed,’’ said Donohue.

Donohue nearly died after being shot by friendly fire during a shoot out with the Tsarnaev brothers on the night of April 18, 2013 in Watertown, Massachusetts. The shootout ended with the death of Tamerlan, who was run over by an SUV driven by Dzhokhar as he attempted to speed away from the scene.

“When people think back on the events of April 15, 2013, they won’t remember your name,” Rebecca Gregory, who refused to acknowledge her words as a “victim” impact statement, said. “It’s funny that you smirked in the courtroom and flipped off that camera, because that’s what we’re doing to you today.”