Three men from China allegedly stole a Japanese tourist's credit card and tried to use it to buy a branded watch at a Paragon boutique last Saturday, a court heard.

When the transaction could not go through, they left the shop.

But the trio were nabbed before they could leave the country - police arrested them at Changi Airport in a four-hour-long sting operation on Monday.

Among the $29,000 worth of items seized from them were a range of foreign currencies, wallets, belts, bags, watches and perfumes.

Police believe the men are part of a pickpocketing syndicate, which targets tourists and use stolen credit cards to buy luxury goods.

Yesterday, Zheng Ding Wen, 48, Li Aibin, 50, and Zhang Xiaobao, 53, were charged with taking part in a conspiracy to cheat.

They are accused of presenting a credit card that did not belong to them for the payment of an Omega watch at Watches Of Switzerland at about 11am last Saturday.

As a result, a shop employee was deceived into giving them the watch. It is not known if the men left the shop with the watch after the card payment was unsuccessful due to a system error, or if they had returned it. The cost of the watch was not stated in their charge sheets.

According to police, a sales assistant had found their behaviour suspicious and made a report.

Officers traced the card to a Japanese tourist, who realised his wallet was missing only when contacted. He made a police report.

Officers from the police's Central Division and Commercial Affairs Department conducted ground inquiries and surveillance between Saturday and Monday. The trio were then arrested at the airport between 11.45am and 1.50pm.

It is not known how many tourists Zheng, Li and Zhang had allegedly cheated, at which locations they allegedly pickpocketed their victims, or how long they had committed their alleged crimes.

The case will be mentioned again next Wednesday.

The maximum punishment for cheating is 10 years' jail and a fine.