Sony's PlayStation hit by hack attack

Users are unable to access Sony's online PlayStation store

A hacker group has claimed responsibility for attacking Sony's online PlayStation store, which is down on Monday.

Visitors to the site are greeted with a message that says "Page Not Found! It's not you. It's the internet's fault".

A group called "Lizard Squad" has taken credit for the outage, posting "PSN Login #offline #LizardSquad" as their Twitter status.

The outage is the most recent in a series of attacks on tech giant Sony.

The Japanese firm's Hollywood film studios' corporate network was hacked into last month, followed by an online leak of unreleased movies, along with confidential information such as actors' salaries.

Sony Entertainment Network has responded by tweeting that they are aware of the issues that users are having in connecting to the PlayStation network.

"Thanks for your patience as we investigate," the company tweeted at about midnight GMT.

The disruption comes just days after the gaming console celebrated its 20th anniversary last week.

Lizard Squad's Twitter page

Lizard Squad attacks

Meanwhile, the outage on the PlayStation network follows one on Microsoft Xbox network, which was down for at least a day last week.

Lizard Squad also claimed it was behind the attack.

The Xbox network was hit with a DDOS, or a distributed denial of service attack, which overloaded the system, stopping users from getting online.

The hacker group had then said that its Xbox attack was just "a small dose" of what was to come over the Christmas season.

Lizard Squad has claimed responsibility for attacks that have taken high-profile targets like EA games and Destiny offline in the past.

Known as Lizard Patrol on Twitter, the anonymous collective has a Russian-based website.