SW side of SAPD blocked with crime scene tape #KENS5Eyewitnesspic.twitter.com/Wzv1VvjjIf

— SueKENS5 (@SueKENS5) November 20, 2016

SAN ANTONIO — A police officer was fatally shot in the head while sitting in his squad car writing a ticket Sunday morning.

The cop pulled over a car near police headquarters at about 11:40 a.m. when a driver in a second car pulled up behind him and shot the officer twice, according to KENS5 News.

The killer shot the officer once through the window before reaching into the car and shooting him again.

He was still on the loose Sunday.

The officer, who had 20 years on the force, was pronounced dead at San Antonio Military Medical Center. His name was not released.

A black sedan was spotted leaving the scene.