A K-9 with an Arizona police department was fatally shot by a suspect in the line of duty Friday night, the department said.

The dog, named Koki, with the El Mirage Police Department was chasing 38-year-old Joe Ruelas about 5:20 p.m. when the suspect opened fire, according to FOX 10 Phoenix.

“Tonight we had a very serious situation in our city in which our K9 Koki was killed protecting his fellow officers,” Chief Paul Marzocca said in a statement posted to Facebook after the shooting.

After Ruelas struck Koki, two officers returned fire on the suspect, who fled the scene, the report said.

But soon after, police discovered Ruelas dead from an apparent self-inflicted gunshot wound.

Ruelas was being sought for aggravated assault when he initially fled from cops.

The department on Saturday posted an emotional video tribute to Koki on Facebook, showing various photos of the K-9 with his handler out in the community.

“Thank you for your service K-9 Officer Koki. You are a true hero,” the video was captioned.

The posts were met with an outpouring of support.

“I’m so sorry to hear of your loss,” one woman commented. “My heart goes out to all the officers, but especially to Koki’s handler.”

Another user said: “God bless you K9 Koki and your fellow officers. THANK YOU for serving and protecting El Mirage and the surrounding communities. I am so incredibly sorry for your loss.”