Geocachers find trinkets and trouble

Hobby using GPS to discover hidden containers prompts additional police scrutiny

When the Loudoun County sheriff's deputy stumbled on the green ammunition can hidden in a Sterling drainage pipe, he did the right thing. He called in the bomb squad.

It turned out to be a false alarm. The bomb techs opened the box and found a few small trinkets, a notebook and a pen inside. It wasn't an ammo box at all. It was one of about 939,000 active "geocaches" worldwide.

Geocaching, an online game in which players use global positioning devices to track down hidden containers at coordinates posted on a Web site, is soaring in popularity.

But what might seem like a harmless hobby is causing increasing consternation for law enforcement. Police and emergency responders must be wary of any suspicious packages in this region. So they are trying to keep a watchful eye on the phenomenon, warning gamers to exercise caution and training officers to recognize the devices.

"It is something that has raised some concerns," said Loudoun sheriff's spokesman Kraig Troxell. "They're everywhere."

For their part, the high-tech treasure hunters are seeking to coexist in this post-Sept. 11 society. They say they take precautions and reach out to police in a sometimes vain effort to avoid the kind of misunderstandings that brought out the bomb squad last week.

Geocachers hide their stashes, big and small, at selected locations to create a range of difficulty levels. Some clues lead the hunters deep inside nature preserves, across rivers or high on mountains, but sometimes the boxes are hidden in plain sight or in downtown neighborhoods.

Caches usually come in a canister that can be mistaken for something more sinister. "The green ammo cans are great because they're virtually rust- and waterproof, but you can't see inside of them," said Chris Hughes, 49, president of the almost 900-member Northern Virginia Geocaching Association. "To minimize angst, we cover up the military-looking serial numbers. You can buy brightly colored geocaching stickers."

Geocaching usually enters police lexicon after it's linked to the report of a suspicious package. Baltimore County police spokesman Bill Toohey had never heard the term until his bomb squad "neutralized" a geocaching site in a residential neighborhood.

"It caused considerable disturbance because it was what looked like a bomb in a playground," Toohey said. "It wasn't a game. This was a very alarming situation."

Geocaching has sown police confusion across the country. A small container at a sports store in Kentwood, Mich., in August; a package containing cash and a transponder taped to a trash can near Chicago in May; and a suspicious package sitting in a mesquite grove in Midland, Tex., in July 2008 brought a massive police response.

Loudoun is the only Washington area jurisdiction with any significant geocaching issues. In Prince William County, the police intelligence unit has forwarded alerts to officers about the game, said Sgt. Kim Chinn, a spokeswoman.