Circle Internet Financial lost $2 million to email fraudsters in an “incident” that occurred last month, the payments company said in Thursday regulatory filings.

The “email fraud incident” did not impact customer funds and accounts, and Circle’s “information systems” remained secure, Circle said. It said the unnamed fraudsters stole $2 million in “company-owned funds” in June 2021. 

Circle made the disclosure as part of its preparation to go public through a merger with a special purpose acquisition company. The $4.5 billion payments company is positioning itself to be Wall Street’s highest-profile stablecoin specialty firm.

Circle did not elaborate on the incident in its SEC filings. A spokesperson declined to comment.