A Nassau County cop was struck by a car and seriously injured today, police said.

The unnamed officer was injured at 11:40 a.m. on the Nassau Expressway at the intersection of Seagirt Blvd. In Lawrence.

“The officer made a vehicle and traffic stop” just before being struck, one officer said. “He suffered multiple injuries.”

After the accident, the injured officer was airlifted by helicopter to Nassau University Universal Medical Center in East Meadow, where he was reported in serious condition.