A man was left with life-threatening injuries Wednesday afternoon, after a bike-riding suspect stabbed him as he stood on the sidewalk.

The 29-year-old male victim was standing on the 400 block of Turk Street, which is between Larkin and Hyde Streets, at 1:55 p.m. Wednesday. Suddenly, according to the San Francisco Police Department, a man in his 40s rode up on a bike.

The cyclist, police say, "jumped off [the] bike, chased [the victim], and stabbed" him with a knife.

The suspect then jumped back on his bicycle and pedaled off, police say.

The victim was transported to San Francisco General Hospital in serious condition, police say. An update on his condition was not available as of Thursday morning.

The suspect, police say, remains on the loose today, and no arrests have been made in the attack.