Guests at a San Francisco fast food joint were stunned Sunday, when a man entered the restaurant and started stabbing a patron.

According to the San Francisco Police Department, the 36-year-old victim was "eating alone" at a restaurant on the 1600 block of Valencia Street, which is between Mission and Cesar Chavez Streets at 3:19 p.m. Sunday when the attack occurred.

Police say that suddenly, a 42-year-old male suspect entered the restaurant and "began stabbing [the victim] before fleeing the scene."

A reader who contacted SFist asserted that the stabbing occurred at the Burger King restaurant at 1690 Valencia Street.

"A friend came upon the scene shortly after it happened and knew the person who was seated next to the man who was stabbed," the tipster wrote. "He said the man looked very disfigured and lost a lot of blood. He wondered if he would live since he was stabbed from behind in the head neck and chest."

The reader's friend can rest easy, police say, as the victim survived. He was transported to San Francisco General Hospital with wounds that are not considered life-threatening, according to the SFPD.

In addition, police say that his alleged attacker was later arrested, and has been booked into San Francisco County Jail. As of Tuesday afternoon, further information on any motive in the stabbing had not been released, nor were any additional details on the suspect available.

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