Jaclyn Vargo, the director of the Department of Education’s investigative arm, has abruptly left the job after four years, officials told The Post.

Vargo led the Office of Special Investigations, OSI, a unit that probes educators accused of corporal punishment against students and other employee wrongdoing.

“This came out of left field. She’s gone,” a co-worker said, adding that colleagues were not given an explanation.

Some underlings believe Vargo was “fired” or “terminated,” but DOE officials said she simply quit and insisted she was not forced to leave as the result of any alleged failure or wrongdoing.

“We thank Jaclyn for her service to the DOE,” said spokesman Douglas Cohen.

Vargo could not be reached for comment.

Her departure comes two weeks after OSI took over bus-driver misconduct investigations, which formerly were conducted by the Office of Pupil Transportation.

She also leaves after a tug of war over control of the Special Commissioner of Investigation, another city agency that investigates misconduct in city schools.