Police are searching for the driver of an SUV who allegedly struck a man and sped away early Wednesday in Inwood.

Authorities said Robert Johnson, 58, was hit by a fast-moving SUV at the corner of Mott Avenue and the Nassau Expressway at approximately 1 a.m.

"Witnesses report that the vehicle slowed, almost came to a stop and then drove off," Nassau Det. Lt. Mike Fleming said.

Johnson, a longtime support staff employee at the Nassau County District Attorney's Office, sustained two broken legs, a broken arm and serious head trauma. He is in critical condition at South Nassau Communities Hospital in Oceanside.

"We do have some parts recovered at the scene and we are working to try to narrow it down, the make and model of the vehicle," Fleming said.

To cross the six-lane highway, pedestrians said one must reach the other side in less than 30 seconds.