A beach goer at Cardiff State Beach noticed the military ordnance in the sand Sunday afternoon and took it to a lifeguard tower, Sheriff's Department Sgt. Roberto Lopez said.
Members of the sheriff's bomb arson squad rendered the unidentified explosive safe and disposed of it, the news website U-T San Diego reported.
The section of the beach where the incident occurred was later reopened, and the beach opened as usual Monday morning, the Los Angeles Times said.
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