A female trader was robbed of what is believed to have been HK$3.5 million in cash in a deal involving the cryptocurrency Tether as well as the mobile phone that stored the tokens.
This is the second cryptocurrency-related robbery case in two weeks.
Police are looking for four men in their 20s and 30s, including one who posed as a buyer, who fled in a pickup truck from the Kwun Tong location where the deal was being made.
The four made off with the cash after the Tether tokens had been transferred to the "buyer's" digital wallet.
The trader told officers the transaction was carried out in a Kwun Tong industrial unit on Chong Yip Street at 3pm yesterday.
As she was counting the cash, which had come in HK$1,000 banknotes, three armed men with knives and batons, believed to be accomplices of the buyer, came in, took the money and mobile phone, and fled with the buyer after locking the door.
The woman called her uncle, who located her with his phone's GPS tracker and lodged a report to police.
Officers activated an operation codenamed "Exigent," deploying officers to possible escape routes to track down the getaway vehicle.
Police said one of the robbers is about 170 centimeters tall, fat and wore light-colored clothing and a hat, while the other two were black-clad.
Tether, also known as "stablecoin," was originally pegged at US$1 (HK$7.80) per token.
But the cryptocurrency became controversial in 2019, when its value fell to US$0.47 per token. This came as reports surfaced that Tether had allegedly manipulated the value of its rival Bitcoin, lacked a long-term banking relationship and failed to prove adequate reserves.
A series of robberies involving cryptocurrency deals have been reported across the city in recent years.
On January 4, a 37-year-old male trader trying to cash in on the surge in Bitcoin was robbed of around HK$3 million and two phones minutes after being lured into a deal in Chai Wan.
In January 2018, a 34-year-old male buyer was robbed of HK$1.4 million in cash following a Bitcoin transaction hoax in North Point.