A Lake Ronkonkoma man was arrested for allegedly stealing a car, assaulting a police officer and trying to steal a marked police vehicle.

Officers say it all happened Saturday morning at around 7 :30 a.m. on School Street in Ronkonkoma.

Police say the victim was driving on School Street when William Gilmartin jumped on the vehicle’s hood.

According to police, the two then got into an argument, with the driver getting out of the car. Gilmartin then allegedly jumped into the driver’s seat and drove away, all while the vehicle’s owner was holding onto the car door.

The victim was dragged for more than a block before being thrown off, police say.

Officers say they were able to locate Gilmartin at his house on Arlington Road, where he attempted to leave. While they tried to place him under arrest, he punched a sergeant in the face and ran off, police say.

They say Gilmartin then tried to steal a marked police patrol vehicle, when another officer Tasered him.

Gilmartin pleaded not guilty to charges of robbery, grand larceny, reckless endangerment, resisting arrest and assault on a police officer. He was released on $5,000 cash bail.

"He's never been in trouble before," said Gilmartin's attorney Matthew Tuohy, who also spoke to News 12 Long Island about how he plans to defend his client.

"Right now, we're looking into certain medical issues, certain underlying medical issues that are going on," Tuohy explained.

Gilmartin is due back in court on Aug. 10.

Police say the sergeant and driver of the car are expected to be OK.