Xbox Live is online again after suffering an outage Monday around 8 p.m. ET, with a hacker group claiming to have DDOSed its servers, reports the Inquisitr.

The alleged antics left some gamers in the United States and Canada unable to connect to the service.

Lizard Squad has claimed responsibility for the Xbox Live attack on Twitter, tweeting, "That's a small dose of what's to come on Christmas. #LizardSquad."

The group or individual behind the Lizard Squad has been very busy, taking credit on Twitter for the "Destiny" outage. The online-only shooter game was down for four hours in late October and, according to Down Detector, on Nov. 22.

Lizard Squad also claimed to be behind disabling the PlayStation's Battle.net and other services earlier this year.

The method of attack used by Lizard Square is called a Distributed Denial of Service (DDOS). It is a form of attack that overwhelms a server with requests so that it can no longer respond to legitimate user requests. In the Xbox Live attack, Xbox 360 users were completely out of service, while Xbox One users were able to sign on but not access their friends list. The Xbox Support page was disabled in the attack as well with the page displaying a runtime error.

Lizard Squad is promising more attacks on Xbox Live over the Christmas holiday.

According to the Inquisitr, Lizard Squad has not released an official statement or reason behind the attacks on Xbox Live or other services. It is unknown if they are protesting anything or attached to any cause.

For now, Xbox Live appears operational. The Xbox Live status page reports no problems.