Thieves may soon have a harder time trying to break into mailboxes.
The U.S. Postal Service or USPS told FOX40 they are in the process of upgrading security features on cluster mailboxes.
"It's just frustrating because there's not much we can do about it," Rose Lewis said.
Lewis lives at the Oakridge Townhomes on Edgebrook Drive in Modesto. She says her neighborhood's cluster mailbox was broken into last Tuesday, for the third time in recent months.
"There was no sign of breaking and entering just, doors were wide open," neighbor Mark Kollmeyer said.
Neighbors showed FOX40 photos they took of the mailbox with it's main door wide open, after they say it was broken into.
The U.S. Postal Service said they suspected the thief who broke into the box used counterfeit master key to open the front of the mailbox, or somehow attained a legitimate master key. USPS Spokesperson Jeff Fitch said it's a method they've seen in other cities like Sacramento, Stockton, Fresno and Bakersfield.
Fitch said USPS is working on replacing master locks on all cluster mailboxes. He said USPS is also working on replacing some current cluster mailboxes with new, higher security models.
Fitch said USPS would not release a schedule of what locks will be replaced when, to prevent publishing a road map for criminals.
"In the meantime that doesn't help us, you know?" neighbor Elizabeth Silveira-Crow said.
Neighbors said they were taking security into their own hands, pointing a surveillance camera at the cluster mailbox in their neighborhood.