Santa Ana authorities were investigating a possible pipe bomb explosion early Wednesday at a hardware store.
Law enforcement officers responded to a report of an explosion around 9 a.m. at an Orchard Supply Hardware at 1975 East 17th St.
Witnesses said they heard a blast near the exit doors of the store, the Santa Ana Police Department said in a statement.
No injuries were immediately reported.
When investigators arrived they said they found what appeared to be remnants of a pipe bomb at the store's exit.
The area has been evacuated and the Orange County Sheriff's Department bomb squad was en route.
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