Chinese police have apprehended 125 suspects allegedly involved in an online gambling network, the public security department of northeast China's Heilongjiang Province said.

About 230 million yuan (37 million U.S. dollars) was frozen and about 80 million yuan has been confiscated by police so far, with dozens of gambling websites and payment platforms shut down.

The gambling mega-den caught the attention of police in Mudanjiang City in Feb. 2014.

An investigation showed that gambling activities were manipulated by a group named "Dafa 888" in the Philippines. Established in 2002, "Dafa 888" has operated online gambling in several Asian countries.

According to police, the group has attracted gamblers from more than 10 provinces in China. Some lost more than one million yuan, and one even forced his daughter into prostitution for gambling money.

The principal criminal, whose surname is Wang, was escorted back to Harbin on Saturday night, an official with the department said.

The case is under investigation.

Gambling has been illegal on the Chinese mainland since 1949.