A Brooklyn federal judge sentenced a Saudi-born al-Qaeda terrorist to life in prison Friday for killing two U.S. troops in Afghanistan.

“I can’t think of a more serious crime,” U.S. District Judge Brian M. Cogan said as he handed down Ibrahim Suleiman Adnan Harun’s sentence in the New York City courtroom.

Harun, who describes himself as an al-Qaeda “warrior” who acted as a soldier and not a terrorist, refused to attend his Friday sentencing and his trial last year.

“This is not my court. That is not my judge,” Harun, 47, reportedly told prison officials, according to the judge.

The judge refuted Harun’s claim, saying that the defendant intended to kill “dozens or maybe hundreds of Americans” and potentially those of other nationalities.

“I’m confident the defendant doesn’t differentiate whether they are civilians or soldiers,” Cogan said. “If this man ever walks the streets again, the first thing he will do is try to kill Americans. He has one gear. That’s to kill Americans.”

The Saudi-born terrorist had been convicted in March for his role in a 2003 ambush in Afghanistan that killed Army Pvt. Jerod Dennis of Antlers, Oklahoma, and Air Force Airman Ray Losano of Del Rio, Texas.

Prosecutors say he confessed while in Italian custody to throwing a grenade and firing at an American military unit in the 2003 ambush. Harun was extradited from Italy to the U.S. in 2012.