Authorities in Taiwan have broken up an illegal online gambling ring that catered to local gamblers as well as punters on the Chinese mainland.

On Friday, Taiwan’s Central News Agency reported that the country’s Criminal Investigation Bureau (CIB) had raided multiple locations in Taichung City on Wednesday, arresting 33 individuals suspected of involvement in the illegal online sports betting operation, which focused primarily on European football matches.

CIB officials said their investigation had determined that the site had been in operation since last December. Since that time, the betting site had handled wagers totaling NT$340m (US $11.3m), averaging around NT$2.25m per day.

The CIB fingered a man identified only as Tseng as the brains behind the operation, which reportedly employed over a dozen people working in three shifts around the clock. These staffers were responsible for recruiting customers through social media and text messaging services, as well as setting up bank or Alipay accounts through which Chinese customers’ bets would be deposited and any winnings paid out.