On Thursday, Microsoft's Xbox Live online gaming service was not accessible for many of its users due to a denial of service attack. While it's now back up and running, a newly revealed hacker group which calls itself Phantom Squad claimed responsibility for Thursday's downtime, and claims it will shut Xbox Live and Sony's PlayStation Network service next week as well.

Ars Technica reports that Phantom Squad made the claims and threats on its Twitter feed which has since been shut down. It says the attacks were to show that Microsoft and Sony don't spend enough on their online security. During the holiday period of 2014, another hacker group, Lizard Squad, launched denial of service attacks on both Xbox Live and PlayStation Network, which made it hard for people who got new Xbox One and PlayStation 4 consoles as presents to go online on Christmas Day. Several members of Lizard Squad were later arrested.

It should be noted that denial of service attacks, which consist of a flood of useless online traffic from thousands of dedicated PCs, don't indicate how secure a network like Xbox Live is from truly malicious attacks.

Source: Ars Technica