On Sunday, Sony's PlayStation network was shut down for several hours after it was overwhelmed with artificially high traffic, i.e. it was the target of a distributed denial of service (DDoS) attack.

The network is now back online, and according to a Sony blog post, there is no evidence that users' personal information was compromised. 

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Still, it was a deeply unsettling weekend for the company. On Sunday, a group claiming responsibility for the cyber attack via the Twitter handle @LizardSquad also sent out a tweet suggesting there was a bomb threat on an American Airlines flight from Dallas-Fort Worth to San Diego carrying Sony Online Entertainment President John Smedley. "Awesome. Flight diverted to Phoenix for security reasons," Smedley tweeted, later elaborating:

A Sony spokesperson told the BBC that the FBI was investigating the bomb scare.

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Lizard Squad said in a tweet that it acted in order to pressure Sony to spend more money on its network: "Sony, yet another large company, but they aren't spending the waves of cash they obtain on their customers' PSN (PlayStation Network) service. End the greed."

Sony wasn't the only gaming service targeted over the weekend; Blizzard Entertainment (developers of World of Warcraft) and Riot Games (developer of League of Legends) also reported disruptions. Lizard Squad claimed responsibility for these attacks, too.  

Sony's PlayStation network was the target of a major cyber attack back in 2011 -- the network was down for more than a month after hackers infiltrated the service, not just shutting it down but also compromising credit card information and other personal data from over 70 million user accounts.

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