PHNOM PENH (AFP) — Cambodian authorities have arrested more than 200 Vietnamese nationals in internet scam center raids, police said Wednesday, as Prime Minister Hun Manet ordered a crackdown on cybercrime sweatshops.

The United Nations has described Southeast Asia as the “ground zero” of scam centers, where workers typically use romance or business cons to defraud social media users of an estimated $40 billion annually.

Hun Manet issued a directive made public on Tuesday, telling law enforcement and the military “to prevent and crack down on online scams,” warning they risk losing their jobs if they fail to take action.

Police in the capital Phnom Penh said they raided two buildings housing scammers on Monday and Tuesday, arresting 149 Vietnamese nationals alongside three Chinese citizens and 85 Cambodians.

In the coastal city of Sihanoukville, raids on Tuesday at four locations saw 63 Vietnamese nationals arrested and 54 computers seized, according to a police report seen by Agence France-Presse on Wednesday.

Many of those freed from Southeast Asian scam centers say they were trafficked or lured there under false pretences.

Abuses in Cambodia’s scam centers are happening on a “mass scale,” a report published last month by Amnesty International said.

There are at least 53 scam compounds in Cambodia where organized criminal groups carry out human trafficking, forced labor, child labor, torture, deprivation of liberty and slavery, the report said.

In March, Cambodia deported 119 Thais — among 230 foreign nationals detained during raids on alleged cyber scam centers in the border city of Poipet.

The United Nations Office on Drugs and Crime warned in April that the scam industry was expanding outside hotspots in Southeast Asia, with criminal gangs building up operations as far as South America, Africa, the Middle East, Europe and some Pacific islands.