BOSTON  -- Boston Marathon bomber Dzhokhar Tsarnaev has been sentenced to death today by a jury in a Boston federal courthouse.

Tsarnaev was convicted by the same jury of seven women and five men last month of all 30 counts related to the deadly April 15, 2013 bombing. Three people were killed, including an 8-year-old boy, and another 260 were injured when Tsarnaev and his older brother, Tamerlan, detonated twin explosive devices near the finish line of the marathon. Three days later, the brothers murdered MIT police officer Sean Collier.

Tamerlan Tsarnaev was killed in a shootout with police four days after the explosions. The jury today found death the penalty was "appropriate" for six of the 17 death penalty eligible counts against Dzhkohar Tsarnaev.

"The jury has spoken. Dzhokhar Tsarnaev will pay with his life for his crimes," U.S. Attorney Carmen Ortiz said following the verdict.

Tsarnaev's father, Anzor, told ABC News from Dagestan after the verdict, "We will fight. We will fight. We will fight until the end."

During his trial, Dzhokhar Tsarnaev pleaded not guilty, but his defense said from the start he would not shirk responsibility for his role in the blasts –- only that he did it while under his older brother’s influence. Legal analysts at the time said the defense was designed to set up a similar tactic in the death penalty phase of the trial in order to win Tsarnaev life in prison.

In a front page Op-Ed for the Boston Globe, the parents of Martin Richard, the eight-year-old killed in the blasts, argued for the government to drop the death penalty and give Tsarnaev life in prison “to end the anguish.”

“As long as the defendant is in the spotlight, we have no choice but to live a story told on his terms, not ours,” Bill and Denise Richard wrote. “The minute the defendant fades from our newspapers and TV screens is the minute we begin the process of rebuilding our lives and our family.”

Liz Norden, the mother of two men who each lost limbs in the blast, told ABC News recently, "I want to see him die for what he did to my boys."

After the verdict was read, the Richards sat stonefaced with their eyes downcast. Norden wept.

“We know all too well that no verdict can heal the souls of those who lost loved ones, nor the minds and bodies of those who suffered life-changing injuries from this cowardly attack," Attorney General Loretta Lynch said in a statement. "But the ultimate penalty is a fitting punishment for this horrific crime and we hope that the completion of this prosecution will bring some measure of closure to the victims and their families."

ABC News' Dada Jovanovic and Tanya Stukalova contributed to this report. Michele McPhee is a Boston-based freelance reporter and frequent contributor to ABC News.