SAN DIEGO — There’s a consumer alert for Mira Mesa residents. Thieves are taking personal checks out of mail boxes and cashing them.

It happened at least twice in recent months at the U.S. post office on Mira Mesa Blvd.

In April, neighbor Barbara Reynolds mail a $400 check to the state tax board.  The agency never received it.

“I just drove up in my car and dropped it off,” said Reynolds.

Days later, a man tried to cash the same check in San Juan Capistrano.

“The check was washed and rewritten,” Reynolds said.

Luckily, the bank became suspicious and refused to cash the check.

Still, Reynolds said it was a major hassle getting her taxes and banking back in order.

“I had to close my account. I had to sign up for another one. It takes time for that. It's very time consuming,” she said.

Just last week it happened again at the same Mira Mesa post office. James, who didn't want his last name used, said he mailed a check early in the morning at the Mira Mesa office. Four hours later, he said, someone tried to cash it at a bank across the street.

“The check was to pay the phone bill. It was around $70 and when he went to cash it, he had changed it to $1770. Thankfully the bank caught it,” James said.

The crime is called mailbox fishing, where thieves use a device to reach inside the mailbox and steal envelopes.

“My girlfriend said she saw a bunch of mail laying on the ground two weeks earlier at about 4:30 in the morning with some kind of cardboard contraption stuck inside the box,” said James.

The U.S. Postal Inspection Service said customers can drop off mail inside the post office. And, if you do use a mailbox to mail checks, drop off envelopes shortly before the pickup time printed on the box. Even better, consider paying bills online instead of mailing checks. You can also write your checks using pens with pigment ink that cannot be washed off.

“My advice is don't deposit your mail in one of these (mailboxes), especially if it's a check,” said Reynolds.

The postal inspection service said the agency is aware of the recent thefts at the Mira Mesa post office.

If you are the victim of mail theft, report to the crime by calling the U.S. Postal Inspection Service at (877) 876-2455