MADISON, Wis. -

A woman from downtown Madison told police she was sexually assaulted by a stranger while she was walking alone.

The 22-year-old victim told police she was walking in the 100 block of Langdon Street at about 12:20 a.m. on Sept. 6 or Sept. 7 when a man grabbed her from behind, put an arm around her neck and punched her in the stomach.

She said she was groped over her clothing. She said she was screaming and might have injured the man during the assault.

The man fled toward Wisconsin Avenue after she fought back, according to the victim.

The attacker is described as white, in his mid-to-late 20s, 6 feet to 6 feet 2 inches tall, weighing 175 to 185 pounds with a medium build. He was wearing a blue sweatshirt and shorts.

The woman said she was initially reluctant to report the assault but was encouraged by a friend to report it.