Newark, N.J. - Ali Muhammad Brown, 34, of Seattle pleaded guilty today to the 2014 killing of Brendan Tevlin, 19, of Livingston, N.J. Tevlin was gunned down while sitting in a car at a stop light. He was home from his freshman year of college.

Brown also stunned the courtroom today during jury selection for his murder trial, when he admitted to killing 3 men in Washington state for the purpose of jihad. Charges in those murders are still pending in Washington.

“He was seeking to have a mission of vengeance against the United States,” said Essex County Assistant Prosecutor Jamel Semper. “It appeared that he wanted to make himself something of a martyr. He is not. He is just an admitted killer who destroyed lives and hurt families."

In Essex County, he’s facing life in prison for terrorism, murder, carjacking, robbery and weapons charges. This is the first time ever in New Jersey that a terrorism conviction has been attached to a murder charge. Brown will be sentenced on May 1.

He is currently serving a 35-year sentence for a separate armed robbery he committed in West Orange.

The Associated Press contributed to this report.