The protesters entered the building, owned by the Archdiocese of San Francisco, at 888 Turk St. after a late-afternoon rally and march Sunday.
Demonstrators said that the two-story building had been vacant for five years and that they planned to use the space to offer medical services, food and housing to the community.
The archdiocese released a statement today saying that the properties at 888 Turk Street and 930 Gough Street have been used by Sacred Heart Cathedral Preparatory High School. They said the building had been used for music and art classes as recently as 18 months ago.
According to Jesse Smith, one of the protesters who occupied the building, neighbors told the group that the building had been abandoned for five or six years and that they were happy to see the space being utilized.
The archdiocese said that they plan to use the properties to produce revenue to assist students from low-income families.
Police began to arrest the demonstrators at around 1:15 p.m. and a police spokesman said the protesters retreated into rooms and the doors were barricaded.
Officers saw protesters on the roof with chairs, buckets of paint and piles of bricks and were concerned that these items would be used as weapons against police, spokesman Sgt. Michael Andraychak said.
One protester leaped from a second story window onto a Gough Street sidewalk where he was detained by officers, Andraychak said.
Andraychak said police discovered graffiti on the interior and exterior of the building that read "Burn It Down," "New Social Order" and "Kill Cops."
Smith said the building was damaged before the protesters arrived.
"There was definitely damage to the building long before we got there," he said.
He said the bricks were already there and that while it was possible that the demonstrators were responsible for some of the graffiti, he didn't see anyone do it.
The protesters who were arrested were taken to county jail for processing and were cited for trespassing and released, police said.
Demonstrators marched this evening in solidarity with those arrested.
The group left City Hall at around 6 p.m. and marched along Market Street to the Hall of Justice, where they greeted the protesters who had been detained with food, Smith said.