International Pickpockets Ride New York’s Subway, Pilfering and Profiting The thieves are not known to the police, which helps them evade detection. They also move from city to city, trying to stay ahead of investigators.

In Manhattan alone, transit larcenies were up 15 percent in 2018, with 754 reported cases.

A man and woman walked out of a subway car at the 51st Street station in Manhattan and darted into the next one on the same train. A plainclothes police officer noticed.

It was rush hour on a Tuesday evening in September on the busy No. 6 line. The officer watched as the woman dipped her hand into a commuter’s purse while her partner stood in front of her, shielding her from view, according to the officer’s affidavit. The woman lifted out a wallet, and the officer and his partners closed in.

She threw the wallet to the ground, and the commuter quickly identified it as hers. The woman, Jenny Gomez Velandia, 27, and her accomplice, John Diaz-Albarracin, 31, were arrested, according to a criminal complaint. What seemed like a routine pickpocketing had been thwarted.

But the suspects were not routine. Unlike most pickpockets, they had no criminal history in New York City. They were not locals. They were from Colombia and had come to New York for the purpose of stealing wallets on subways, one of several international pickpocket rings to descend on the transit system in 2018, the police said. “They come, they do what they can do, then they move,” said Chief Edward Delatorre, who leads the Police Department’s transit bureau. The woman and man arrested in September were tied to nine other thefts in the subway, the police said.

Little is known about these international pickpocket crews outside of the narrow scope of their crimes, the police said. They tend to avoid detection longer than their local counterparts because they are new faces, and their lack of criminal histories in the city is to their advantage when they are caught. They move from city to city, trying to stay ahead of investigators.

A three-man ring from Chile worked the No. 7 train in Queens during the United States Open last summer, when the platforms were extremely crowded, the police said. The three were finally caught in Manhattan. On Aug. 28, a straphanger on an uptown No. 4 train “felt himself being jostled” by a man beside him wearing a black bag. He realized his wallet was gone, and he told officers at the 59th Street station, who arrested the man with the bag, Victor Diaz Jimenez, 33, according to a criminal complaint. He was carrying, among other things, three MetroCards and four phones.

“I’m used to this,” Mr. Jimenez later told the police, according to court documents. “Everywhere I go, every country kicks me out.”

He described his methods. “This is how I make my living,” he told a detective. “I open the purses, put my hands in and take the wallets out. I pick people who are distracted.” He recalled lifting a wallet from “a tourist on the green line.” He took stolen credit cards to Target to buy watches he sold on the street, he said, and if the card had already been reported stolen, he threw it away.

“I’ve only been here for two weeks,” he said.

The police also arrested two teenagers who worked with Mr. Jimenez, Michael Camilo Joya Pinzto and Jhon Quintero Santos, despite Mr. Jimenez’s claims that he did not involve them in his work.

That group, like the Colombians, was tied to other crimes: nine previous grand larcenies in Queens and Manhattan — and in Mr. Jimenez’s case, elsewhere in the country. The police discovered an open arrest warrant for Mr. Jimenez from Kansas City, Kan., where he was wanted for charges of larceny and identity theft, according to prosecutors there. Mr. Jimenez remains on Rikers Island, facing a possible extradition to Kansas, and he declined a request for an interview.