A woman is fighting for her life after she was stabbed during a South of Market mugging on Saturday morning, officials say today.

According to San Francisco Police Department spokesperson Officer Gordon Shyy, a 30-something woman walking near Fremont and Folsom Streets at 5:30 Saturday morning was approached by a man who "demanded her property," Shyy says.

When the woman told the mugger that she didn't have anything of value on her person, he stabbed her in the upper body, Shyy says.

Shyy says that the woman was transported to San Francisco General Hospital, where she's being treated for critical injuries as a result of the attack.

The suspect, who police describe only as a Hispanic man in his 20s, fled and remains at large, Shyy says.