On March 26, Bui Huy Hoang and a woman accomplice, whose name has not been revealed, entered a store in Kanuma City and allegedly stole cosmetics and other items valued around 130,000 yen ($1,166), the Tokyo Reporter said Sunday.
After committing the crime, the duo fled in a vehicle.
Later that day police in Tochigi Prefecture apprehended the pair following a complaint from the store owner that foreigners had stolen from his shop.
According to the police, the gang, comprising Vietnamese, targets drugstores in Tochigi and is believed to have carried out more than 70 robberies.
The reputation of Vietnamese living in Japan took a hit following a police report in 2017 that said they committed more crimes than any other foreign non-permanent residents in the country
They recorded 5,140 crimes by Vietnamese people in 2017, up from 3,177 the year before, accounting for 30.2 percent of all crimes committed by foreign nationals.
Shoplifting was their main crime, with 2,037 cases, while the number of burglaries they committed shot up to 325 from just 12 the previous year.
The number of Vietnamese living in Japan jumped by 26.1 percent from a year earlier to 330,835 in 2018, accounting for 8 percent of foreign nationals, the Japan Times reported.
Vietnamese have overtaken Philippine nationals as the third largest minority group behind China and South Korea.