Hong Kong: Six people had been arrested for robbing 51 million Yen (about 330,000 US dollars) of cash at Hong Kong's Sheung Wan on Friday, the Hong Kong Police Force said on Saturday.

The suspects, five male and one female, aged between 23 and 52, had been detained on suspicion of robbery, the police said, adding that more arrests are likely.

The police said that on Friday morning, two employees of a Japanese precious metal company were carrying 190 million Yen of cash for currency exchange around Des Voeux Road Central in Sheung Wan when two men snatched a backpack containing 51 million Yen from them. The two men fled the scene in a getaway car.

Around six hours after the incident, the police arrested the two alleged robbers of Japanese nationality, along with a female accomplice, who were carrying 4.6 million yen of the stolen cash at the Hong Kong International Airport, Xinhua news agency reported. Two male employees of a cryptocurrency exchange were arrested later on suspicion of assisting in the disposal of stolen cash.

The police also tracked down another 7 million Yen at a money changer.

A 27-year-old Japanese man who reported the robbery was detained after police investigation revealed that he was the alleged inside man. His contradictory statements alerted the police, who had been suspicious of the unusually precise timing of the snatch and grab.

Japan's leading Kyodo News Agency reported further investigation revealed that one of the Japanese victims, 27, who filed the report to police was actually an accomplice and provided inside information.

"The perpetrators seemed to have a very good grasp of the victims' driving route and arrival time," said Superintendent Sam Sin.

As of Saturday afternoon, police had recovered around 11 million yen and did not rule out further arrests.

The Japanese Consulate General in Hong Kong said its nationals were victims of a crime but did not provide details.

The area is lined with currency exchange shops. In the Sheung Wan district in December, employees of a Japanese company dealing in luxury goods were robbed of around 1 billion yen in cash while heading to exchange money, Kyodo News Agency reported.

Seventeen Hong Kong men and women have been arrested, but the cash has not been recovered.

The police, the report mentioned, have yet to see any relation between the December robbery and the latest case.