A man who intervened in a dispute between two family members is behind bars this morning, after he allegedly attacked one of the arguers with a hammer.

Police say that the incident occurred at 12:40 a.m. Friday, near the intersection of Division and Brannan Streets. According to the San Francisco Police Department, a 55-year-old man "and his family member got into altercation," and the suspect, a 49-year-old man "interfered to stop it."

This interference, police say, angered the older man, who then confronted the suspect. During that confrontation, according to the SFPD, the suspect picked up a hammer and hit the older man, then fled the scene.

The victim was transported to San Francisco General Hospital for treatment of his injuries, which police say are life-threatening. According to the SFPD, they were able to identify and track down the suspect, arresting him and booking him into San Francisco County Jail by early Friday morning.

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