ver since the invention of money and ways to carry it, there have been thieves inventing clever ways to steal it.

Cedric Mitchell, a Metro Transit Police detective, knows all about the ancient crime of pickpocketing.

Summer, he says, is prime time for pickpockets. They like to go where the big crowds gather: street fairs, air shows, malls, museums, airports, ballparks and subway trains.

"They're looking for people with money on them who are naive, or who are not paying attention to their surroundings," said Mitchell, who has been with Metro for 16 years. He's seen victims both old and young.

"Kids as young as 12 years old get hit. Pickpockets know there's money there," Mitchell said. "Parents send kids on these class trips to Washington with $400 or $500."

Mitchell teaches transit police and other law enforcement officers how to spot pickpockets. The crooks try to blend in, he said, but they often give themselves away.

"It will be sunny out, with no chance of rain, and yet they're carrying a trench coat, which they use to hide what they're doing with their hands," Mitchell said.

Clothing on a hanger in a dry cleaning bag works the same way. "Watch for somebody carrying dry cleaning downtown at 6:30 in the morning," Mitchell said. "People generally pick up their dry cleaning close to their home, in the afternoon."

Pickpockets generally work in groups. Each person has a special job. The stall creates a distraction, while another person, the wire, grabs the wallet or purse. The distraction could be anything: pretending to know the victim, pretending to be deaf and need help.

"They like to work escalators," Mitchell said. "One of them will be at the bottom of the escalator pretending to drop his glasses. When people all start bumping into each other on the escalator, that's when they make the play [pick the pocket]. People expect to be jostled in this situation, so they don't notice when it happens."

Pickpockets move from neighborhood to neighborhood, and city to city, leaving when police catch on to them. They came for Washington's round of inaugural parties in January and for Baltimore's Preakness horse race last month, Mitchell said. The men's college basketball Final Four in April was crawling with pickpockets -- police in Minneapolis, Minnesota, made seven arrests.

Right now, Mitchell is leading a special anti-pickpocket detail that covers the D.C. region.

"Once we make a few good collars [arrests], word'll get around and they'll disappear for a while," he said. "But they'll be back."

-- Fern Shen

Detective Cedric Mitchell shows police how to spot pickpockets.