St. Paul police are asking for the public's help in identifying a man suspected of repeatedly punching a woman and raping her overnight.

Police on Thursday released a photo of the suspect captured on surveillance camera. Sgt. Mike Ernster, a police spokesman, said the man is suspected of assaulting a woman either late Tuesday or early Wednesday near 4th and Commercial streets just outside of downtown's Lowertown neighborhood.

Investigators are still piecing together details of the assault, because the woman's memory was affected by blows to the head, Ernster said.

"She's groggy from the assault and head injury," he said.

According to police: the woman, who is in her 30s, had recently become homeless. She was walking downtown when she encountered the suspect. They two began talking, and the man talked her into accompanying him on walk to the store.

The two began walking, and the woman realized they were moving away from the store. The man punched the woman in the face multiple times, and she became disoriented, Ernster said.

The suspect then sexually assaulted her.

Ernster said it's too early to determine whether the man is suspected in any other attacks.

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

Chao Xiong • 612-270-4708

Twitter: @ChaoStrib