CAMBRIDGE (CBS) – Police in Cambridge are searching for the man who randomly attacked three people in Cambridge this weekend. The victims are speaking exclusively to WBZ-TV.

The first man who was sucker punched is a Harvard postdoctoral fellow in neurobiology, with a black eye and cut face.

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“I didn’t get knocked out which was nice, I didn’t black out or anything,” he says. “So I was able to get up pretty quickly.”

We are not using his name, but the man was the first of three victims sucker punched and knocked to the ground on Mass. Ave. Saturday afternoon by the same assailant.

It’s the guy seen on video attacking a man walking with his girlfriend just outside a furniture store, a girlfriend still trying to come to terms with the random violence. “To me he just seemed mentally disturbed,” she says. “He seemed under the influence he was listening to music really loud and he was just walking around yelling.”

“I could tell within one or two seconds before he hit me that something was a little bit off with this guy,” the first victim said. “Periodically you’ll be walking the street and you can tell something is off with some guy but nothing happens they just walk by.”

Instead, the odd stranger served up a fist in the face and would do the very same thing to a Tufts visiting scholar a few minutes later.

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“It was really shocking, surprising for me because I thought that Boston was a quiet city,” he said. In fact, the suspect punched him three times, mumbled something incomprehensible, and then calmly walked away. “He was mad, crazy man. Because there is no reason to do something similar.”

All of the victims were attacked within a few minutes of each other in the 900 block of Mass. Ave. and all suffered cuts and bruises to the face.

The assailant is a black man in his 20’s wearing a black coat, dark knit cap, and blue jeans with a black sling-style backpack. His motive remains a mystery.

“There’s nothing I could have done differently, really,” said the first victim. “There was no time to react.”

Police are hoping someone can ID the suspect before he really hurts someone.

“It could have been a lot worse, I suppose,” the first victim said. “But this is probably the worst weekend I’ve had in a long time, possibly ever.”

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