It happened around 8:15 p.m. Tuesday at Route 40 and Porter Road in Glasgow, Delaware.
Police say the officer was traveling east on Route 40 when he entered the intersection of Porter Road with lights and sirens on. That's where he was struck broadside by a pick up truck traveling south.
The officer was trapped in the wreckage.
Once finally free, the officer was airlifted to Christiana Hospital in stable condition with a head injury.
The officer's name has not been released, but Action News has learned he is 35 years old and a 12 year veteran of the force.
The driver of the pickup truck was not seriously injured.
The shooting the officer was responding to happened in the 3300 block of Stone Place in the Village of Kent Apartments in Bear.
There, a 30-year-old man had been shot in the head. He was rushed to Christiana Hospital in critical condition.