DALLAS (AP) — A former suburban Dallas police officer charged in the killing of a 15-year-old black boy when he fired into a moving vehicle carrying five teenagers, has testified at his murder trial that he had no option but to use lethal force.

Roy Oliver, who was fired from the Balch Springs Police Department after the shooting in April 2017, told jurors Thursday that he decided to shoot when he saw the vehicle move toward his partner. The gunfire killed high school freshman Jordan Edwards.

Oliver says he thought his partner was in danger. His partner, Tyler Gross, previously testified he did not fear for his life and never felt the need to shoot.

A prosecutor previously called Oliver "trigger happy."