The crash happened at around 4:30 p.m. Thursday in Scarborough.

Police say Trooper Ryan Keller was in the median in the northbound side of the highway helping a driver who was stuck. The driver of a truck failed to notice the slowing traffic, swerved to avoid the stopped cars and hit the back of Keller’s cruiser.

Keller suffered a cut on his head. He was treated and released from Maine Medical Center.

The crash is being attributed to the driver’s inattention but no one will be charged.