United States Postal Service inspectors confirmed they are investigating a break-in that took place on Sunday at a post office in Pleasanton, where an unconfirmed number of large postal boxes were broken into.

Postal Inspector Jeff Fitch told the Weekly that the crime happened at 4300 Black Ave. on Sept. 26, but he said did not have details about what time it occurred, how many suspects were involved or how many victims were affected.

"I talked with the supervisor of our mail theft team; they're already investigating so there's already an investigator that's actively working on this," Fitch said. "I'm sure an investigation will determine what time the attack took place."

According to Fitch, each of the affected box holders will be contacted by USPS, who will work with them to determine what was taken from each postal box.

Anyone who has their mailbox or contents broken into or stolen is advised to report the crime and keep an eye on their credit card and bank statements over the following month for signs of unauthorized use.

"It's not just when the break-ins happen; it's three or four weeks down the line when you get your credit card transaction statements," Fitch said. "Convenience stores, department stores that financial information is being used at are critical to helping identify the individuals responsible for the break ins and thefts."

Mail theft is a federal crime and carries a potential penalty of up to five years in a federal penitentiary or a fine up to $250,000. A standing reward of up to $10,000 for information leading to the arrest and conviction of those responsible for the crimes is offered.

Anyone with information about the break-in at the post office on Black Avenue is asked to call the USPS dispatch number at 877-876-2455.