Following the cyber-attack on Xbox Live last week, hackers have now targeted Sony Entertainment Network. A notorious group that calls itself Lizard Squad appears to take credit for temporarily taking down PlayStation Network on Sunday, as it posted on its Twitter account, "PSN Login #offline." 

This isn't the first time that the group targeted Sony's gaming platform. The cyber-vandals also claimed responsibility for previously using "distributed denial of service" to take down the gaming network back in August, as well as for stirring up a bomb scare on a plane that had Sony executive John Smedley on board. 

This is another blow for Sony, as the company's filmmaking arm, Sony Pictures Entertainment, was also hacked by another group last Nov. 24. The cyber-security breach compromised the company's data and left its computer system paralyzed. Five stolen movies were made available online for download, and more than 47,000 Social Security Numbers were reportedly stolen. The invasion of Sony Pictures was done by a group that calls itself GOP or Guardians of Peace, which did not only steal data but also sent threatening emails to Sony employees. 

Initially, there were speculations that the hacking of Sony Pictures was due to North Korea's retaliation against the company's upcoming comedy "The Interview," which features an assassination attempt against the nation's leader Kim Jong-Un. The North Korean government, however, denied responsibility although they reportedly said that it was a "righteous deed." The hacking of Sony Pictures is currently still under investigation. 

Meanwhile, a petition has been started asking the White House to stop Lizard Squad. The petition has so far gathered more than 7,800 signatures, with over 92,000 needed by Jan. 4 to reach the target of 100,000.  The group, considered as a nuisance, had also taken responsibility for previously taking down the "Destiny" and "Call of Duty" servers, among others. Only last week, they used DDoS to cripple Xbox Live. 

"Microsoft will receive a wonderful Christmas present from us," the group posted on Twitter. "Just some preparation for Christmas. That's a small dose of what's to come on Christmas." 

In its Twitter bio, the group describes itself as, "The ddos kings formerly known as LizardSquad. Some lizards just want to watch the world burn."