An off-duty police officer shot a man just before 4 p.m. Monday in the Frankford section of Philadelphia, according to authorities.

The incident left a man in critical condition at an area hospital.

It all went down on the 4600 block of Worth Street and possibly was due to a dispute over a parking space, according to witnesses.

Neighbors told NBC Philadelphia's Claudia Rivero that the off-duty officer just moved into the neighborhood. Police say that the officer was actually using his pickup truck to help a relative move into a house on the block.

The off-duty cop, an 18-year veteran of the force, at some point came into contact with a man who had a gun, Philadelphia Police said.

The victim, 23-year-old Josh Taylor, was hit once in the chest and rushed to Aria Hospital Torresdale for immediate treatment. He was listed in critical condition, police said.

He's the father of a 3-year-old son and a 1-year-old daughter, according to neighbors.

Taylor's fiancée Brittney Britton claimed that the officer shot Josh inside their house.

"Next thing you know my boyfriend is running in the house, shuts the door behind him," Britton said. "The cop opened the door fully on his own, no warrant...got in a stance and just shot him right in the chest and ran... right over to his house and shut the door."

Britton says that Taylor had a gun in his pocket but never threatened the officer. Police say that the officer claimed that Taylor had pointed the gun at him.

When police arrived on the scene the officer allegedly pulled out his badge and handed his gun over to the cops who then handed the man his gun back, a neighbor said.

Police Internal Affairs are still investigating the case. The unidentified officer will be put on desk duty pending the investigation.

Part of what police want to find out is why the off-duty cop didn't call for backup after he was allegedly threatened.

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