By Emily Turner

VALLEJO (CBS SF) — A recent rash of mailbox thefts has compromised more than 300 people’s deliveries in Vallejo and now residents are waiting in lines to pick up packages at the post office.

The U.S. Postal Service is investigating the thefts.

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“It’s a shame,” said mailbox owner Larry Greg.

The post office inspector says there have been 23 reported burglaries in the Vallejo and American Canyon area since February 1st and likely more unreported.

Crooks are breaking open some boxes, picking the locks on others and possibly using a counterfeit master key. Once inside, they’ve got your mail, and all the information that comes with it.

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Justin Kegel, another mailbox owner, said, “Nobody needs to get into my bank accounts, my visa accounts, steal my money.”

Mail theft is federal crime and the post office’s law enforcement arm has launched several investigations into the spike. But until the case is solved, folks’ mail will be kept at the post office so that it is kept safe.

“Something needs to be done. I mean we don’t need come down here and wait in line forever… they got to do something,” Kagel.

Mail theft is a federal crime that is punishable with up to five years in prison and $250,000 in fines. Two master keys were also stolen from the post office and may have been used to steal mail. Investigators say the theft of master keys, or duplication of those keys would increase the criminal penalty.

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There is a $10,000 reward offered to anyone who comes forward with information that leads to the arrest and conviction of the person or people behind the thefts.