Xbox Live and PlayStation Network, the online services for Microsoft's and Sony's game consoles, are experiencing intermittent outages apparently due to a malicious distributed denial-of-service (DDoS) attack.

As of writing, the Xbox Live status page is showing Xbox Live Core Services as "limited," while the PlayStation Network service is offline. The connectivity problems began around Christmas Eve and have been acknowledged by both Sony and Microsoft.

"We are aware some users are unable to sign into Xbox Live. Our teams are working to resolve the issue. Visit xbox.com/support for status updates," said Sean McCarthy, general manager of Microsoft's Xbox Product Services, adding that the company doesn't share information on the root cause of specific issues.

On the other hand, Sony's Ask PlayStation account tweeted:

A hacker group by the name of Lizard Squad, that had previously pledged to take down the services on Christmas Day, has taken credit for the attacks via Twitter, promising that it’ll back off once it gets sufficient number of retweets. "Get this tweet 2,000RTS and make sure to follow @iBeZo if you want us NOT to hit XBOX and PSN #offline for the rest of the night! RT," the group said in a tweet which has since been deleted.

Incidentally, this is the same group that took the responsibility for Blizzard and PlayStation Network outages last August, saying that the action wouldn't stop until the US ceased attacks on the Islamic State (also known as ISIS or ISIL). It also tweeted a bomb threat following which the flight of Sony Online Entertainment head John Smedley was diverted.