(BSS/AFP) - Hong Kong authorities have frozen assets worth HK$2.75 billion ($354 million) believed to be proceeds of crime linked to a Cambodian conglomerate whose founder is accused of running forced labour camps, police said.

The US Justice Department unsealed an indictment last month against Chen Zhi, whose Prince Holding Group was accused of serving as a front for "one of Asia`s largest transnational criminal organisations".

The Hong Kong law enforcement action came on the heels of similar moves by Taiwan and Singapore.

Cyberscam hubs have proliferated across Southeast Asia in recent years, luring foreigners to work in scam hothouses that swindle people with online romance and crypto investment cons.

Hong Kong police said on Tuesday they acted after a probe into a "syndicate suspected of involvement in international cross-border telecommunications fraud and money laundering".

Police valued the frozen assets at approximately HK$2.75 billion, which they said were believed to be the proceeds of crime and included "cash, stocks, and funds held by individuals or companies".

Prince Holding Group was the target of the law enforcement measures, a police source told AFP.

No arrests had been made by Tuesday afternoon.

Taiwanese investigators said separately on Tuesday that 25 people had been arrested in relation to the group, with authorities there seizing $145 million in assets.

Singapore police seized more than $115 million in assets tied to Chen last week.

US and UK authorities unveiled sanctions last month freezing Chen`s businesses and properties in both countries, while Washington`s indictment charges Chen with fraud and money laundering involving Bitcoin worth about $15 billion.

The two countries allege Chen directed the operations of forced labour compounds across Cambodia, where thousands of workers were held surrounded by high walls and barbed wire.

Under threat of violence, many were forced to execute "pig butchering" scams -- cryptocurrency investment schemes that build trust with victims over time before stealing their funds.