Arson investigators are at the scene of another suspicious fire that was set early this morning in the Castro neighborhood -- the fourth in the last 24 hours.
On Friday morning, a fire was set outside a home on Collingwood and 18th streets, according to media reports. There were no injuries.
On Thursday at about 5 a.m., three fires were set, one of which displaced 13 residents and destroyed two homes.
The first fire started at 2155 15th St., followed by another fire at 3620
16th St. Shortly after that, firefighters were called to a third fire at 17th and Hartford streets.
The four fires are believed to be the result of an arsonist.
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