The Anchorage Police Department says one of its officers was treated for minor injuries Saturday when the cruiser they were parked in was hit from behind by a woman driving drunk at about 4:30 a.m.

In a community alert, APD says three officers were investigating a traffic incident near the intersection of Lake Otis Parkway and Tudor Road before the crash. The driver of a Jeep Renegade was found passed out in the southbound lane of Lake Otis.

"One officer parked in front of the vehicle, one officer parked behind the vehicle and one officer parked farther north to block the southbound lane for the officers to safely investigate and protect the driver," the alert reads. The police vehicles' emergency lights were on.

As the officers investigated, a Chevrolet Equinox going south on Lake Otis didn't change lanes and crashed into the cruiser that was parked farthest north. The driver kept going and hit the cruiser that was parked behind the Renegade, injuring the officer inside and causing a chain reaction collision.

The driver of the Equinox, identified as 21-year-old Danielle Agnus, was not injured.

Officers conducted field sobriety tests and then took her to jail.  Court documents show Agnus' blood alcohol level was .275, more than three times the legal limit for driving.

The Anchorage Fire Department treated the officer who had injuries to his forehead and shin and evaluated everyone else at the scene.

The other two officers and the driver of the Renegade, who was still inside his vehicle when it was hit, were not hurt.

The Renegade's driver was found not to be impaired. He was driven home by one of the officers, and his vehicle was towed because of damage from the collision.

Police say Agnus faces charges of operating under the influence, third-degree assault and passing/overtaking emergency vehicles.

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