WINDOW ROCK, Ariz. — Navajo Nation President Russell Begaye has ordered all flags in Chinle to be flown at half-staff from sunrise to sunset Saturday in memory of a tribal patrol officer killed in a car crash.

The Navajo Nation Police Department says Leander Frank died Tuesday after he was dispatched to a call in the Tsaile area.

Authorities say Frank’s vehicle collided head-on with another car in the middle of Navajo Route 64 between Chinle and Tsaile.

Tribal officials say Frank was the 12th Navajo Police officer killed in the line of duty since 1975.

They say seven Navajo Police officers were killed by gunfire, three died in automobile accidents, one died after an assault and one succumbed to a heart attack.