A pair of separate attacks in the Mission this weekend left two victims with life-threatening injuries, according to police.

The first incident occurred at 2pm Friday, when a 44-year-old man was stabbed with a knife at 16th and Mission streets. After stabbing the victim, the suspect, a 37-year-old man, ran onto a Muni bus, and the victim chased him. They continued to fight, until police officers arrived and arrested the suspect.

The victim was taken to a hospital to treat life-threatening injuries. Police had no further information on his condition today.

On Saturday night around 11:15pm, a 38-year-old man was punched by another man on the 3200 block of 22nd Street (between Mission and Valencia), according to police.

The victim fell to the ground, sustaining life-threatening injuries. He was transported to the hospital.

The suspect, a 30-year-old man, fled in an unknown direction, and has not yet been caught.