Activist Group Anonymous Hacks Security Firm HBGary

Online hacktivist group Anonymous has taken down the website of a US security firm which claimed to have intimate knowledge about the group's senior members.

Anonymous, which is being investigated for a string of high-profile online attacks on PayPal and MasterCard, reportedly hacked into HBGary's main website and gained access to its e-mail accounts and deleted files. The group also released some of the company's internal documents online.

In a message posted on the compromised website, Anonymous announced that it had "seized" control of HBGary's operations in order to protect its interests.

“You brought this upon yourself. Let us teach you a lesson you'll never forget: don't mess with Anonymous,” the group said in a statement.

The attack happened shortly after Aaron Barr, head of HBGary Federal, claimed he had infiltrated the group and knew the identity of senior Anonymous members. Barr had said that he would release the information he had discovered at a conference in San Francisco.