LOS ANGELES (CBS) — Federal officials launched an investigation on Thursday after four 200-pound mailboxes were stolen in less than a week at multiple San Fernando Valley post offices, potentially leaving postal customers vulnerable to identity theft.

The mailboxes stolen from offices in Pacoima, Glendale and Burbank were bolted into a concrete slab, U.S. Postal Inspector Renee Focht told the Glendale News-Press.

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KNX 1070’s Ed Mertz reports.

No suspects have been named, but the thefts appeared to be a “recent trend,” Focht said.

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Investigators have not confirmed if all the incidences were connected.

Focht advised concerned postal customers to check their credit reports and contact their banks.

All of the mailboxes will be replaced, Richard Maher of the U.S. Postal Service said.

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The agency has offered a $10,000 reward for information leading to an arrest. The public was urged to report suspicious activity at (877) 876-2455 or visit the official website for details.

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