Authorities in Macau have smashed an illegal bookmaking racket that took HK$5bn (¬£379m) of World Cup bets in one week, according to the South China Post.
Police arrested 22 suspects following a raid on an unnamed hotel in the special administrative region of China.
The syndicate were allegedly using three rooms in the hotel as a headquarters, taking bets over the phone and the internet.
A spokesman for the Macau police, Suen Kam-fai, called it the largest betting case in history.
Investigators seized HK$2m in cash along with ten computers, mobile phones and betting slips, one of which indicated a single bet of HK$40m.
A second gambling syndicate was busted in the same hotel hours later, with police arresting four Chinese men.
The raids were part of an international operation, organised by Interpol and the Hong Kong police, who have formed a task force with the Macau and Guandong province authorities to tackle illegal betting across eight Asian countries during the World Cup.
Doha-based watchdog International Centre for Sport Security warned in a May report that Asian-dominated criminal groups are laundering more than US$140bn in illegal sports betting annually.
Last week, 58 people were arrested in Thailand in connection with illegal football betting.