A 23-year-old woman has told police she was grabbed from behind and sexually assault by a man while walking on a street in West Philadelphia.

The attack occurred about 8:30 p.m. Monday on the 100 block of South 47th Street in the Walnut Hill neighborhood, police said Wednesday.

The victim said that after forcing her to the ground, the assailant physically and sexually assaulted her before fleeing with her purse, police said.

The suspect is described as a 30- to 35-year-old black male with a dark complexion, about 6 feet tall with a heavy build. He has short black hair, a close-trimmed beard, and a mustache, according to police. He was wearing gloves, a blue jacket, and a black knit hat and was carrying a backpack.

Anyone with information is asked to call the Special Victims Unit at 215-685-3251.