The Justice Department will seek the death penalty for alleged Boston Marathon bomber Dzhokhar Tsarnaev, Attorney General Eric Holder announced Thursday.

“After consideration of the relevant facts, the applicable regulations and the submissions made by the defendant’s counsel, I have determined that the United States will seek the death penalty in this matter,” Holder said. “The nature of the conduct at issue and the resultant harm compel this decision.”

Tsarnaev, 20, and his deceased brother Tamerlan Tsarnaev, are accused of killing three people and injuring more than 260 others at the annual marathon.

For months, officials have deliberated over whether to seek life in prison or the death penalty for the 20-year-old former college student.

In general, Holder has spoken out against the use of the death penalty but has still sought the punishment in certain cases.

Authorities captured Dzhokhar Tsarnaev last April after a massive manhunt that shut down the streets of Boston for hours. Tamerlan Tsarnaev was killed during a shootout with police.

Both are accused of building and setting off homemade bombs at the finish line of the sporting event.

The younger Tsarnaev has pleaded not guilty to the charges.

In a court filing, federal prosecutors accused the bombing suspect of betraying the U.S. — his home for the last decade.

"Dzhokhar Tsarnaev received asylum from the United States; obtained citizenship and enjoyed the freedoms of a United States citizen; and then betrayed his allegiance to the United States by killing and maiming people in the United States," said U.S. Attorney Carmen Ortiz.

The federal government has executed just three people since 1988 — when it reinstated the death penalty — including Oklahoma City bomber Timothy McVeigh.