UPDATE: Police have confirmed that the backpack was filled with personal items and clothing, not a bomb. Read more details after the jump.
Original story 2:40 p.m.: Police have closed off parts of Civic Center after an unidentified African-American man told federal marshals that there was a bag with a bomb inside it.
At about 12:51 p.m., the man walked up to the marshal on the corner of Golden Gate and Market streets and told him about the bomb before spitting out some sort of antigovernment garble, according to police.
Federal marshals called local police and firefighters, who located the backpack. However, it's not yet known whether an explosive is actually inside the bag, police told SF Weekly.
The following streets have been closed down while police investigate: southbound Polk between Turk and McAllister; Golden Gate between Van Ness and Hyde; and Larkin from Turk to McAllister.
The man was not detained.
We'll tell you more when we learn more.
Update: Police cleared the streets at about 3:20 p.m. after learning that there was no bomb inside the backpack. Federal marshals detained the man who reported the threat. They are still trying to determine whether the backpack was his. It is not yet clear whether officers will file charges against him.
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