Story highlights Driver records the entire interaction with officer after traffic stop

"I'll put a hole right through your head," detective says on video

(CNN) A driver's dashcam video posted to YouTube on Sunday appeared to show an off-duty detective threatening to kill a driver during a stop in a town near Boston.

The detective in question, Stephen LeBert of the Medford, Massachusetts, Police Department, is now on administrative leave pending an investigation after the release of the video , which contains explicit language.

"I'll put a hole right through your head," said LeBert repeatedly, often swearing at the driver as well.

The incident happened Sunday night in Medford, a few miles north of downtown Boston. The driver admits he took a wrong turn at a traffic circle, and LeBert pulled him over.

The driver, a 25-year-old man, who would only call himself "Michael," said he did not realize LeBert was a member of the police when the detective first confronted him. LeBert was off duty and wearing camouflage shorts and a tank top at the time of the incident. LeBert does appear to show his badge at one point, but it's not clearly visible on the video.

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