An Amtrak worker was electrocuted and killed while performing work at a substation in The Bronx on Thursday, police and law enforcement sources said.

The incident occurred at around 11 a.m. at the site at White Plains Road and Unionport Road in Parkchester, where Con Edison and Amtrak have facilities.

The employee was working on an electrical line when he put a ladder up against a transformer that he thought was off, but wasn’t, and got electrocuted, law enforcement sources said.

The worker died at the scene.

Two other Amtrak workers suffered non-life-threatening injuries as a result of the incident.

One of them was taken to Jacobi Medical Center, while the other refused medical attention at the scene.

The incident, which authorities initially called an explosion, caused major delays on Amtrak trains traveling through Penn Station.

“We are deeply saddened to report the death of an Amtrak employee,” Amtrak said in a statement, adding that “a full investigation is underway.”

A spokesman for Con Edison said the incident “has nothing to do with us, but we are here and offering help.”

Additional reporting by David Meyer