A police officer was airlifted to Nassau University Medical Center after being struck by a car north of the Atlantic Beach Bridge just before noon Tuesday, authorities said.
A spokesman says the accident happened on the Nassau Expressway in Lawrence on the approach to the bridge.
The spokesman said the police officer was doing radar enforcement and was out of his car when he was struck by an Audi.
"We believe the vehicle that struck him may have been traveling around another vehicle," said Detective Sgt. Jim Skopek. "Hence, the officer did not see the oncoming car and this vehicle may not have seen him in the roadway."
Police would not identify the officer, but said he's a 29-year veteran of the Nassau Police Department and is in his mid-50s. He's described as a model officer.
"He was out there doing his job when this incident happened," said Nassau Police Benevolent Association President Jim Carver. "It's going to take awhile for him. There's a long road to recovery for this officer."
The officer is currently in critical but stable condition after undergoing surgery to treat injuries including a skull fracture and a pelvis fracture.
The driver of the car, who was driving with his family, remained on the scene and police said criminal charges are not expected.
Carver said the incident was a reminder of how dangerous an officer's job is, and that many drivers tend to forget about the Move Over law in New York state.
"If you see a police officer on the side of the road with somebody pulled over, you're required to move over to give him the room for his safety," said Carver.
The Nassau Expressway was closed in both directions while police investigated.