MIAMI BEACH, FLA. (WSVN) - Police in Miami Beach are searching for a man who, they said, knocked a man unconscious while he was waiting to cross the street.

Surveillance video from Nov. 21 showed a man wearing a light-colored shirt punching 70-year-old Cesar Martinez in the head at the corner of Alton Road and 10th Street.

“He hit me in the head. I fell down, and I broke my nose,” Martinez said. “I got a contusion over here in my head. Somebody came from behind. I didn’t see nobody.”

Martinez had just left a nearby Walgreens when he was attacked, and surveillance video captured the man walk up to punch Martinez. As soon as he punches the 70-year-old, he casually walks away.

Video from a passer-by showed Martinez lying in the street seconds after he was punched.

“It appears to be random, unprovoked,” Miami Beach Police spokesperson Ernesto Rodriguez said. “There was no conversation.”

According to police, Trent Cory, a witness who saw the incident, grabbed his cellphone, followed the man and began recording while a good Samaritan stayed behind to help Martinez.

“He just knocked him out,” he said. “They knocked them out cold, and he was just walking down the road like nothing had happened, so I put the video out hoping to identify him and asked him why he did that, and he just shrugged at me and looked as if he did nothing. It was heinous.”

The man would get away before officers arrived on the scene, but police said they have a good idea of who the subject may be.

“He’s believed to be between 6 feet tall and 6’3,” about 240 pounds,” Rodriguez said. “He was seen in that video wearing a light gray tank top, dark gray sweatpants and also had a backpack on.”

Martinez was taken to the hospital with a broken nose and other injuries. He has since been released and is back at work.

While the search for the man continues, police said they need to public’s help to get him off the street.

“The surveillance video, in this case, speaks for itself,” Rodriguez said. “This is a violent crime, and we don’t know who else this man can do this to.”

If you have any information on this attack, call Miami-Dade Crime Stoppers at 305-471-TIPS. Remember, you can always remain anonymous, and you may be eligible for a $1,000 reward.

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