Hackers broke into gambling “prediction market” site Polymarket’s international exchange and stole an undisclosed amount of user funds, CNBC reported on Thursday, with one source telling the network that the incident originated with UK-based web performance monitoring firm and Polymarket vendor DebugBear.

The incident affects Polymarket, the international crypto-based site, and not Polymarket US, the federally regulated exchange that like competitor Kalshi has been accused of violating state gambling laws across the country, according to Wired . Polymarket and Kalshi have also been accused of enabling rampant insider trading , ranging from run-of-the-mill profiteering on inside corporate info to presidential pardons and military strikes .

Throughout Thursday afternoon, some traders reported seeing unauthorized withdrawals from their accounts. Polymarket wrote on X that the exchange had been switched to “cancel-only mode” just after 2:00 p.m.…