Heat from the fire set off the ammunition at the house on North California Street, between Chandler and Burbank boulevards, according to Capt. Peter Hendrickson with the Burbank Fire Department.
The call came into the Burbank Fire Department shortly before 5 p.m.
“We went into defensive mode and applied structure protection to the house and houses next door,” Hendrickson said.
Firefighters put water on the blaze until it cooled down, he said.
No injuries were reported. The cause of the fire is still under investigation.
A damage estimate was not immediately available.
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