Bank of America has fired back at Warminster-based law firm O’Neill Bragg & Staffin, which sued last month alleging the bank was liable for failing to cancel a wire transfer made to China after the firm’s account was infiltrated by hackers.

The firm filed a complaint May 18 in federal court in Philadelphia, claiming the bank was responsible for the damage done after hackers used deceptive emails to dupe a member of the firm into transferring more than a half-million dollars from the firm’s Interest on Lawyer Trust Account to the Bank of China, purportedly on behalf of a client. The complaint claimed the bank breached its contract with the firm by failing to cancel the wire transfer once it was discovered to be fraudulent and by using other clients’ funds from IOLTA sub-accounts to cover the amount.