MINNEAPOLIS (WCCO) — Police are investigating six cases of what they say is a new phenomenon: violent mob attacks on innocent people in downtown Minneapolis.

READ MORE: Maple Grove Man Convicted Of Murder In Wife's Shooting Death

The attacks have happened in the last two months. While there have been some arrests, most of the cases are not solved.

Peter — who asked that we not use his last name — was severely beaten as he walked with his cousin to a hotel in downtown Minneapolis on the night of St. Patrick’s Day. He was in the hospital for three days and is unable to drive because of a brain injury.

Minneapolis police had twice as many officers on duty in downtown Minneapolis St. Patrick’s Day. However, as Peter walked his cousin back to his hotel on Marquette and 7th at 11:45 p.m., he doesn’t see any patrols.

“I don’t remember anything,” Peter said.

The next thing he knew he was waking up in the hospital three days later. He was told 20 young people had attacked him and he had a brain injury.

READ MORE: ‘Our Business is Down Over 50%’: Deadly St. Paul Bar Shooting Impacts Surrounding Businesses

“They said I had been severely beaten, like, in the back of the head,” Peter said. “I didn’t know what my name was when I woke up. I gave them a different name.”

Peter’s mother, Grace, said the ordeal has been terrifying.

“He was already laying down on the ground and they kept kicking him,” said Grace. “He was so sad. He’s a good man.”

While Peter’s case is unsolved, police did make four arrests in the attack on two bicyclists last weekend. The two were attacked by a mob at 5th Street South and Nicollet Mall and were chased down 6th Street South by police. Antonio Jones and three juveniles were arrested after they knocked over items on the Oceanaire Restaurants patio.

Minneapolis Police Inspector Kris Arneson said police are now adding extra foot patrols and cameras on the Nicollet Mall.

“I really don’t know why it’s happening right now, but we are trying everything we can to curb it and stop it,” said Arenson.

MORE NEWS: None Hurt After Shots Fired Inside Plymouth Movie Theater

Arneson stressed that if you look at all the people who come downtown, these attacks are affecting a very small number of people. These mob attacks have happened almost exclusively on weekend nights and early mornings.

Esme Murphy