Police are investigating a stranger rape at gunpoint in St. Paul on Tuesday night and asking anyone with information to come forward.

Officers were patrolling the Payne-Phalen neighborhood about 11:45 p.m. when they saw a woman who was nude run across a street. She went into a yard, where a man — who turned out to be her boyfriend — came out and was comforting her as she screamed and cried hysterically, said Steve Linders, a St. Paul police spokesman.

The officers asked if the woman was injured or needed medical attention. The 41-year-old told them she had just been raped, and she was taken to Regions Hospital for evaluation.

The woman reported she had been walking on Payne Avenue near Geranium Avenue about 11:30 p.m. Tuesday when a minivan pulled up next to her and the driver asked if she needed a ride. She ignored him and continued walking.

Then, she heard something behind her, turned around and saw the driver was out of the vehicle and following her. He motioned with his head toward his hands and she saw he was holding a black semi-automatic handgun, Linders said.

The man told her not to scream or draw any attention to herself and threatened to shoot her if she didn’t do what he instructed.

The man forced her to walk to his minivan, which was parked on Geranium Avenue, and raped her inside the vehicle while threatening her with the gun, Linders said. After the attack, the man drove about half a block and told the woman to get out and not look back.

The suspect is described as a black male, about 6 feet tall, with a medium build. He was wearing a black ski mask, a heavily-worn baseball cap over a stocking cap, black pants and possibly a lighter-colored coat over a sweatshirt.

The vehicle was a newer tan or light-colored minivan with no rust. It had a sliding rear door on each side.

“Police are looking for any information, including surveillance footage, witnesses and certainly the suspect,” Linders said Wednesday.

Anyone with information is asked to call police at 651-266-5685.