Chinese police, with the collaboration of tech giant Tencent, arrested several members of a video game cheating developer ring.

The police in the Chinese city of Kushnan shut down a large cheat development ring that was making more than $70 million a year in subscriptions, according to the BBC. In a Chinese social media post, Tencent called the gang “the world’s largest game cheating ring.”

The police arrested 10 people, who are accused of developing 17 different cheats, charging $10 a day, or up to $200 a month to subscribers.

As online gaming becomes mainstream, there’s an increased demand for cheats. Gaming companies routinely ban thousands of cheaters on their platforms, and the biggest companies in the world now develop sophisticated anti-cheat systems, and employ anti-cheat researchers.

The arrested cheat developers purchased several sports cars with their profits. The police seized the luxury cars including Rolls Royces, Ferraris, Lamborghinis which were worth millions of dollars, according to Tencent.

At the press conference announcing the arrests, the police displayed a plaque that said “Strike like thunder, clean the net, crack down on illegal activities, govern together,” according to Tencent’s post on Weibo.