Hackers have claimed responsibility for a cyber-attack on Sony's PlayStation and Microsoft's Xbox game consoles.
The attack hit gamers on Christmas Day, and some users continued to report problems today.
The attack was claimed by a group called Lizard Squad, while another group, calling itself Finest Squad, said it was trying to get the games back online.
"I have the nation on strings," Lizard Squad wrote on its Twitter site. The group flooded Xbox and PlayStation servers with sustained Denial of Service requests.
"Xbox and PSN have been restored. Give it about 30min to an hour for full service", Finest Squad responded.
But frustrated users took to Twitter to vent their disappointment and anger at Lizard Squad, which also claimed responsibility for attacks on the PlayStation Network and Xbox Live earlier this month.
"Is Microsoft going to reimburse us for the live time that we're missing out on that most of us paid for .. #xboxlivedown #Microsoft," wrote one user.
"PSN has been down for the past 48 Hours, my kids can't enjoy their Christmas present.#ChristmasRuined," wrote another.
Neither Sony nor Microsoft have confirmed the attack. But PlayStation and Xbox confirmed the outages of their networks, adding that they were working to restore the service.
"We're aware that some users are having issues logging into PSN - engineers are investigating," PlayStation said via its Twitter account.
A message on the Xbox Support Twitter account said: "We're aware users are having issues logging into XBL & are actively working to resolve."