Tflow, Sabu, Topiary, and Ryan Ackroyd (known as "Kayla") collaborated in February 2011 on a cyber-attack against Aaron Barr, CEO of the computer security firm HBGary Federal, in retaliation for his research on Anonymous and his threat to expose members of the group. Using a SQL injection weakness, the four hacked the HBGary site, used Barr's captured password to vandalize his Twitter feed with racist messages, and released an enormous cache of HBGary's e-mails in a torrent file on Pirate Bay.[78] The e-mails stated that Barr and HBGary had proposed to Bank of America a plan to discredit WikiLeaks in retaliation for a planned leak of Bank of America documents,[79] and the leak caused substantial public relations harm to the firm as well as leading one US congressman to call for a congressional investigation.[80] Barr resigned as CEO before the end of the month.[81