Detroit — A gang of sexual predators struck twice Thursday night, police said, when in separate instances it forced couples into alleys at gunpoint, and then raped the women while the men were forced to watch.

Police believe the same group may be responsible for a third incident July 11 that featured similar circumstances.

Both of Thursday’s assaults happened in the 13000 block of West McNichols, just west of the Lodge Freeway on the city’s west side, Deputy Chief Charles Fitzgerald said.

“It’s horrifying,” he said. “You try to teach people to walk in pairs, and (the victims) did.”

The first incident happened at about 10 p.m. A 21-year-old female and 22-year-old male were walking when they were approached by six men, who were also on foot, Fitzgerald said.

“One of the suspects produced a gun, pointed it at both victims and advised them to go to an alley,” he said. “Both victims complied. They were forced to the ground.

“The male victim was forced to watch the female victim get sexually assaulted. Their clothing was taken.”

Less than two hours later, in the same area, two men approached a 19-year-old female and 21-year-old male and at gunpoint ordered them into a nearby alley, where they raped the woman while the man was forced to watch. Their clothing was also taken, Fitzgerald said.