A 16-year-old boy was fatally stabbed while walking with a friend in San Francisco’s Ingleside district Monday, police said.

Victor Zheng, of San Francisco, was found with a stab wound to his chest at Capitol and DeMontfort avenues around 10:55 p.m. He was transported to San Francisco General Hospital, where he was pronounced dead, police said.

The victim and a friend were walking on the sidewalk when an 18-year-old man came upon them. The suspect punched Zheng multiple times “without provocation,” then began to walk away.

Zheng and his friend followed the suspect while calling police.

“The suspect noticed he was being followed, turned and then stabbed the victim,” police spokesman Officer Albie Esparza said.

The 18-year-old, described only as an Asian man, remains on the lam, Esparza said.

A motive for the attack was not immediately known. It was unclear whether the suspect knew Zheng, Esparza said.

The homicide was the 12th in San Francisco this year.

Anyone with information about the killing is encouraged to call the Police Department’s anonymous tip line at (415) 575-4444.

maldax@sfexaminer.com