A New York State trooper’s claim that he was shot in the leg during a Long Island traffic stop last week is now under investigation — due to “certain inconsistencies” tied to the case, authorities said Monday.

Cops had been hunting for a gunman ever since Trooper Thomas Mascia, 27, reported he was struck by a bullet during the stop on the Southern State Parkway in West Hempstead last Wednesday night.

But a State Police spokesperson on Monday said that investigators were now no longer looking for the Dodge Charger that Mascia said was involved in the ordeal — and that they had launched an internal probe.

“State Police is conducting an investigation into the circumstances of the shooting involving Trooper Mascia that was reported on October 30,” police said in a statement.

“This remains an ongoing investigation and further specifics are not being released at this time.”

Authorities also executed a search warrant at the injured trooper’s home first thing Monday, cops said.

Nassau County District Attorney Anne Donnelly said her office was “actively investigating certain inconsistencies” tied to the shooting.   

Police sources said that investigators are looking into whether Mascia had actually shot himself.

Mascia, who was released from the hospital last Friday to much fanfare, was said to now be undergoing a psychiatric evaluation, according to the sources.

The trooper had reported that a suspect had opened fire on him as he approached the vehicle parked on the parkway’s median at about 11:30 p.m.  

“Shots fired! Shots fired! I’m hit! I think my kneecap is broken,” Mascia said on the police radio.

The trooper said he thought the driver needed help and wrote down the license plate — “997636T” — before hopping out of his cruiser.

Another trooper responded to his call for help and rushed an injured Mascia to the Nassau University Medical Center where he underwent surgery.

Investigators last week put out a $10,000 reward for any information tied to the shooting, as police and the trooper’s union quickly condemned it, saying the perp needed to be “brought to swift justice.”

“We are sickened by the actions of this cowardly individual who thought nothing of shooting a Trooper who was simply doing his job,” the PBA union’s statement said.

“We thank the medical providers who are providing our brother with the care he needs, and we will support him as he makes what we hope is a speedy recovery.“This incident underscores the dangers our members bravely face every day in service of all New Yorkers and is a reminder that any interaction has the potential to turn deadly.”

— Additional reporting by Craig McCarthy and Larry Celona