On a cool morning last winter, a friend of mine ran across two black plastic garbage bags among randomly scattered mail along the side of the road. "Litterbugs!" she thought at first. But stamped, delivered mail? No Postal Service bags? Some opened, some not? She realized she had stumbled onto something much bigger.

She picked it up and returned home. All of the mail was addressed within a two block area about a mile away. She got the phone book out and began calling those individuals. And local law enforcement authorities.

Mailbox theft. Thieves collect delivered mail (or sometimes outgoing mail) to find out what they can about you. About your identity. Account numbers, Social Security numbers, names, addresses, phone numbers -- enough to open an account somewhere or create a bogus check with your name on it.

They use it themselves or sell it to others. It's a cottage industry and the masterminds may be local -- or may be a continent away.

Although I couldn't find any statistics, mailbox theft is clearly on the rise. Any postal worker or security firm will confirm this. It's part of a nationwide outbreak in identity crime. And you Millionaire Zone readers out there should take note.

Before you put the flag up

Now I'm not suggesting abandoning the United States Postal Service altogether. It does a good job overall and it's a heck of a lot cheaper than FedEx or UPS. You just need to be careful, especially with sensitive mail. And especially if you use a traditional roadside mailbox at the end of your driveway.

Northern California security specialist Defender One offers five precautions:

Consider a locking mailbox.

If you live in a community association or among a group of homes, consider installing a locked community mailbox. Or you can also get attractive and functional locking individual mailboxes, offering a slot for the mail carrier to use without a key. Check out offerings from the Steel Mailbox Company.

Use online bill pay.

I recently wrote about bill pay as a way to simplify your life, save postage and improve security. But if you're mail is vulnerable, I'd step up efforts to convert. Paying online protects twice -- once for incoming bills and once for outgoing checks. One commentator likened putting mail in a mailbox for a day to putting your most vital information in a shoebox at the curb. Not far from the truth. And about electronic payment security -- it isn't perfect, but it's come a long way. If you're careful, your online payments should be safer than mailbox-delivered mail. "Careful" means, for instance, avoiding transactions on public PCs that may have been tampered with, like in a hotel business center.

Deliver outgoing payments by hand.

Unless your mailbox is in sight and you're home all day, you should drop your payments off at a mailbox or the post office. I've been doing this with tax payments for years, but handling the rest this way is not a bad idea.

Get a post office box.

A post office box will also do the trick and should be considered if a locking mailbox won't do or if your situation is especially vulnerable. It's usually tax deductible if you run a business or are self-employed.

Always hold mail delivery when on vacation.

Even if you have someone taking care of pickups for you that mail can stay in the box for a long time and observant crooks will notice you're gone.

Stealing or tampering with mail is a federal offense. But that hasn't been much of a deterrent so far. You probably take your mail for granted, and have for years and years. Just know that thieves are counting on that. Play it safe.

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