More than 800 people suspected of being cross-border scammers were arrested in a joint police operation by Myanmar and China, the junta and Beijing's embassy in Yangon said on Monday.  

Scam compounds have flourished in Myanmar, staffed by citizens from China and other countries who are often forced to work swindling their compatriots in an industry analysts say is worth billions.

Beijing -- a major ally and arms supplier of Myanmar's isolated junta -- has repeatedly asked the military to crack down on such operations. 

Chinese law enforcement provided input to their Myanmar counterparts, who launched raids around Muse city, a major trade hub in northern Shan state, the embassy said on its WeChat channel.

Myanmar police arrested 807 people "who committed cross-border crimes" and seized computers, mobile phones and "fraud scripts", it said in a statement.

Among those arrested in the late March operation were 352 Chinese citizens, who were transferred to China on Sunday, the statement said.

The remainder were Myanmar nationals, it added. 

A junta statement released late Monday said 352 Chinese citizens had been arrested in the swoop and handed over to Chinese authorities.

It said 486 Myanmar nationals had been arrested.

Last year, the United Nations human rights office said at least 120,000 people were being held in scam compounds in Myanmar.

Many were housed in the town of Laukkai in northeastern Shan state, which has since been captured by an alliance of ethnic minority armed groups. The alliance said it would wipe out the scam compounds. 

More than 40,000 people suspected of taking part in cyber scams in Myanmar were handed over to China last year, according to Chinese state media.