New surveillance video is raising big concerns about how thieves are getting access to mail in the South Bay.
Neighbors in Sunnyvale report thieves have taken mail several times before getting into mailboxes again over the weekend.
"It's really scary these people are doing something like this just steps from your home," Sunnyvale resident Zackary Lee said.
Lee said this past weekend's theft is the third time thieves have hit the area in weeks.
"You'd come out to get your mail and you'd see junk mail scattered on the ground," Lee said. "And the thieves had picked through the most valuable mail and left the doors wide open."
Lee is worried the thieves made off with private financial information, including W-2 forms that could put him at risk for identity theft.
The United States Postal inspector is now investigating whether what happened in Sunnyvale is linked to the armed robbery of a mail carrier on Dec. 30 less than a mile away on Sandia Avenue.
"One suspect had a weapon and demanded the keys from the carrier, who gave the keys to the suspect who left the area," U.S. Postal Inspector Jeff Fitch said.
Those master keys can open dozens and dozens of mailboxes in one region, officials said.
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Fitch said there has been a recent increase in robberies targeting mail carriers to get the keys around the Bay Area. The postal inspector reports targeted incidents in Oakland, San Leandro, Berkeley and San Francisco.
The postal inspector said once a key is stolen an investigation is launched and the post office does a security assessment to determine whether to change the locks at large mailbox banks.
Lee said he is concerned about another mail theft and is now considering getting a post office box.
"We're trying to keep a watchful eye and make sure that we don't get our identity stolen," Lee said.