NYPD Officer Jonathan Diller and his partner may have interrupted the planning of a crime Monday evening right before Diller was fatally shot.

The two men may have been casing a store for a robbery in the moments leading up to the fatal shooting, a senior police official told NBC New York.

Officer Diller and his partner made contact with the two suspects, identified by authorities as Guy Rivera and Lindy Jones, because the vehicle the men were in was parked at a bus stop.

When the two officers made contact, Rivera, the passenger in the car, refused to get out. Jones complied with the order and pressed the unlock button on the car door, but Rivera resisted by forcibly closing the door as Diller tried to open it, a senior police official said.

The confrontation escalated and Rivera fired, with the bullet striking Diller in the torso underneath his bullet-resistant vest, police say. Diller's partner returned fire, striking Rivera, who dropped his gun. An injured Diller then rushed to grab the firearm to prevent Rivera from getting it and firing again.

Diller died at a local hospital.

Rivera was shot by Diller’s partner, who fired two shots at the suspect, police say. He was arrested and taken to the hospital for treatment. He is expected to survive and charges are pending.

The driver of the illegally parked vehicle has been charged with Lindy Jones, 41, of Queens, was charged with criminal possession of a weapon and defacing a weapon, Fox New York reports.