Police closed down streets in Potrero Hill after grenades were found in the garage of a 92-year-old man who had recently died.
According to media reports, police have not yet determined whether the possible explosives were real or fake.
At about 7:15 a.m., the grenades were found inside the garage on the 600 block of Potrero Avenue. The street was closed between Mariposa and 19th streets. The area on 18th Street between Utah and Hampshire has also been shut down while the bomb squad investigates.
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