HONOLULU (KHON2) — There is increasing concern over the safety of mail being dropped into blue collection boxes. Officials said thieves are either taking mail out of the blue bins or just taking the whole mailbox even though it’s bolted down.

Officials with the United States Postal Service said mail theft is a growing concern, especially with the holidays approaching. And, those blue mailboxes have become prime targets.

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“We have investigated several instances in the last five to six years where the blue collection boxes were targeted by thieves,” said U.S. Postal Inspector, Brian Shaughnessy. “And in several of these investigations, mail was stolen from those receptacles.”

He said thieves are going as far as taking the whole mailbox.

“Unfortunately we’ve seen over the years that mail thieves will often go to great lengths to steal from the Postal Service and its customers,” said Shaughnessy.

Gilda Muro found that out the hard way when she sent a birthday card to her mom on the mainland.

“I’ve always sent them in the past but at this time she never received them,” said Muro

“And it had gift cards?” KHON2 asked.

“There were gift cards, so she never got her birthday gift cards,” she said.

Shaughnessy said the postal service has improved its security measures but provided some tips that might be helpful.

Each mailbox has the collection times printed on it. Officials said it’s best to get your mail in there before that last collection time of the day.

Also, avoid putting mail in the collection box if it’s a Sunday or a holiday because mail will be in there overnight. Avoid sending cash or gift cards in the mail. If you can, hand the mail to your letter carrier, or drop it in the slots or collection boxes in the post office.

For important mail, advise senders to use the USPS signature services. And, when ordering blank checks, have them mailed to your bank for pickup.

Mail theft is a federal felony crime with a maximum penalty of five years in prison.

“In many of these cases, we are also prosecuting defendants not just for mail theft but for many of the crimes that often come afterward, such as bank fraud, aggravated identity theft and fraudulent use of credit cards,” said Shaughnessy.

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There is a reward of up to $10,000 for information that leads to the arrest and conviction of anyone involved in mail theft.