Lenovo Group said its website was hacked on Wednesday, its second security blemish days after the U.S. government advised consumers to remove software called "Superfish" pre-installed on its laptops. Hacking group Lizard Squad claimed credit for the attacks on microblogging service Twitter. Lenovo said attackers breached the domain name system associated with Lenovo and redirected visitors to lenovo.com to another address, while also intercepting internal company emails.

Lizard Squad posted an email exchange between Lenovo employees discussing Superfish. The software was at the center of public uproar in the United States last week when security researchers said they found it allowed hackers to impersonate banking websites and steal users' credit card information.

In a statement issued in the United States on Wednesday night, Lenovo, the world's biggest maker of personal computers, said it had restored its site to normal operations after several hours.

Lenovo has released software to remove Superfish while pledging to never install it on future shipments.