PORTLAND, Ore. (KOIN) — A man has been sentenced to 70 months in prison after his assault on a Hillsboro police officer left the officer with a broken nose and a severe concussion.

According to the Washington County District Attorney, the assault happened last year on Aug. 19. Authorities say Lt. Neil Potter had just parked his vehicle outside of the Hillsboro Police Department when he was ‘violently attacked’ by Jose Juan Mandujano-Aguilar.

When investigators spoke to eyewitnesses and viewed surveillance camera footage, they found that the lieutenant tried to separate himself from the defendant, who continued to rush the officer and reach for his gun.

In what officials have determined as ‘self defense,’ Potter fired three shots that hit Mandujano-Aguilar in the face and head.

“A review of Lt. Potter’s use of deadly force by the Washington County District Attorney’s Office found the officer was entirely justified and his actions were necessary to save his own life,” District Attorney Kevin Barton said in a release.

Mandujano-Aguilar pleaded guilty to second-degree assault on Friday. He will begin his 70-month sentence at the Oregon Department of Corrections.