St. Paul police are investigating the sexual assault of a woman that occurred Saturday just south of the Wabasha Street Bridge near downtown.

An unidentified man physically assaulted a 20-year-old woman and then sexually assaulted her and threatened to "blow her head off" if she screamed for help, said Sgt. Mike Ernster, a police spokesman.

The attack occurred about 3:15 a.m.

According to Ernster: The woman had taken the light-rail train from Minneapolis to St. Paul and was walking across the Wabasha Street Bridge on the western side when, halfway across, she noticed the man following her.

At some point, the two had a conversation.

"She felt nervous, but talked with him to gauge his intention," Ernster said. "She was walking and trying to keep safe."

The woman told authorities that once she reached the end of the bridge, she started to veer off toward a Holiday gas station located on the corner of Wabasha and Plato Blvd.

The man "suddenly grabbed the shoe out of her hand she was carrying and hit her on the head with it, and pushed her down in the street," Ernster said.

The woman screamed. Her attacker grabbed her and told her he would "blow her head off" if she screamed again, Ernster said. The man did not display a weapon.

Fearing for her life, the woman followed the attacker's orders. The sexual assault occurred in a loading dock area nearby.

The man fled on foot, eastbound on Plato, after the assault. The woman sought help at the Holiday gas station.

Ernster said it's unclear if the suspect is linked to any other assaults, but investigators "are always looking for connections." Police are also looking for surveillance video that may have captured any portion of the incident.

The suspect is described as a black male, 5 foot 6 to 5 foot 9, 30 to 35 years old, wearing a black shirt and gray pants (possibly jeans) and sporting a goatee.

Anyone with information can call police at 651-266-5685.

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