Ho Chi Minh City police on Sunday arrested three people accused of impersonating as sex workers to rob foreigners in the backpackers' area.
Le Thi Lieu, 45, To Van Hau, 22, and Vo Phat Tai, 21, are being investigated on robbery charges, news website VnExpress quoted police sources as saying.
On February 1, the trio allegedly snatched the bag of a French tourist, identified only as a 21-year-old man, when he was sitting on a bench at the September 23 Park in the city downtown.
Lieu and Hau approached the man to rob while Tai was waiting on a nearby motorbike, the police said.
They were caught by plain-clothes police on patrol while attempting to flee.
Police returned the bag with VND23 million (US$1,077), ID papers and other properties to the tourist on the same day.
The trio said during questioning that it was the first time they hatched such robbery plan.
But investigators said they had followed the gang for three weeks. It was the trio that often masqueraded as sex workers to rob unsuspecting drunk foreigners from late evening until dawn, they said.
Further investigations into the gang would be underway, police said.