Police said they raided the centre on Thursday and rescued 383 Filipinos, 202 Chinese and 73 other foreign nationals.
The centre, which is about 100km north of Manila, was masquerading as an online gambling firm, they said.
South East Asia has become a hub for scam centres where the scammers themselves are often entrapped and forced into criminal activity.
Young and tech-savvy victims are often lured into running these illegal operations, which range from money laundering and crypto fraud to so-called love scams. The latter are also known as “pig butchering” scams, named after the farming practice of fattening pigs before slaughtering them.
Thursday’s raid near Manila was sparked by a tip-off from a Vietnamese man who managed to flee the scam centre last month, police said.
The man, who in his 30s, arrived in the Philippines in January this year, after being offered what he was told would be a chef’s job, said Winston Casio, spokesman for the presidential commission against organised crime.
But the man soon realised that he, like hundreds of others, had fallen prey to human traffickers running love and cryptocurrency scams.
Mr Casio said those running the scam centres trapped “good looking men and women to lure [victims]”.
On 28 February, the Vietnamese man escaped the facility by climbing up a wall, crossing a river, and seeking refuge at a farm. The farm owner then reported it to the police.
There were signs of torture on the man, including scars and marks from electrocution, said Mr Casio, whose team visited the man early this month.
Police also seized three shotguns, a 9mm pistol, two .38 calibre revolvers, and 42 rounds of live ammunition from the centre.
Authorities are still in the initial stages of the investigation as most of those rescued from Thursday’s raid are still “shaken”, he said.
In May last year, Philippine authorities rescued more than 1,000 people who were held captive and forced to run online scams inside a freeport zone in Clark, a city also north of Manila – in what remains its biggest bust to date.
A UN report last August estimated that hundreds of thousands of people from around the world have been trafficked to Southeast Asia to run online scams.
Many have said they travelled to South East Asian countries such as Cambodia and Myanmar in response to job ads and promises of perks. They are trapped once they arrive, and threatened if they refuse to participate in the scams. Escapees and survivors have alleged torture and inhuman treatment.
Governments across Asia, from Indonesia to Taiwan, have expressed alarm at the rise in these scam centres. Foreign embassies in countries like Cambodia and Thailand, for example, have issued warnings to their citizens to beware of being lured into scam centres.
China issued public rewards for warlords who were running scam centres across the border in Myanmar – these centres were run by Chinese mafia families and targeted Chinese nationals. Many of those arrested have been handed over to China in recent months.
