A protest group that claimed responsibility for a wave of digital attacks on big U.S. banks in the fall -- including Pittsburgh-based PNC Bank -- apparently has PNC in its crosshairs again.
The al-Qassam Cyber Fighters said in an Internet posting that the group planned a second round of attacks this week on PNC and four other banks -- JPMorgan Chase, Bank of America, U.S. Bank and SunTrust.
This afternoon, PNC started having problems with its website.
"Some PNC customers may be experiencing intermittent difficulty logging into PNC's website on the first attempt," spokeswoman Amy Vargo said in an email.
Pittsburgh's biggest bank was working to restore full access and "will be reviewing the cause of this incident," she said.
In September, PNC's online banking operations were disrupted for a couple of days by the so-called denial of service attacks, which flood websites with communications requests.
PNC "had the longest attack of all the banks," PNC chief executive officer James Rohr said in an interview with CNBC in October.
The hackers "just pummeled us," he said, adding that no customer data was compromised.
In the latest phase, "the wideness and the number of attacks will increase explicitly," the protest group said in a message posted on a website called Pastebin.
The group has said the attacks would continue until a YouTube video insulting the Islamic prophet Muhammad was removed from the Internet.
Patricia Sabatini: email@example.com or 412-263-3066.