A man was seen attacking a Planet Fitness employee in the Rochester, New Hampshire, gym’s parking lot last week.

The video showed an unidentified assailant getting out of his car and begin punching Erin McCarthy, 18, from behind at around 10:00 pm on June 12. Though the publicized tape only captures one punch, police told NECN that the man struck McCarthy 39 times, threw her to the ground, and kneed her in the head before driving off.

“He just kind of came up and hit me in the back of the head and wouldn’t stop,” the victim told WSBK. “He didn’t say a word and he didn’t have a reason behind it. I asked ‘Why? Who are you?’”

A friend took McCarthy to an area hospital. Despite the barrage of blows, she miraculously didn’t sustain any serious injuries.

Authorities also believe the suspect waited outside for the entirety of McCarthy’s eight-hour shift.

“I thought someone was just messing with me and I turned around laughing because I thought they just pushed me in the back of the head. But then I realized it wasn’t joking and he continued to keep beating me,” the teen told NECN.

The Rochester Police Department are now searching for the suspect. He is described as a White male, wearing shorts, a white t-shirt, white sneakers, sunglasses, and a baseball hat. Police Lt. Jeremy Aucoin claimed the man dressed to mask his identity on the night in question.

“It could be a random act or it could be known associates,” Lt. Aucoin told WFXT.

Planet Fitness said they are assisting police in their investigation.

[Featured Image: Rochester Police Department]