Sony's PlayStation Network (PSN) came back online again on Monday, following a cyber attack that made the site inaccessible to users over the weekend.

"The PlayStation Network and Sony Entertainment Network are back online and people can now enjoy the services on their PlayStation devices. The networks were taken offline due to a distributed denial of service attack. We have seen no evidence of any intrusion to the network and no evidence of any unauthorized access to users' personal information," writes social media senior manager Sid Shuman in an official PlayStation blog.

He also assured the public of zero information breach.

"Although this has impacted your ability to access our network and enjoy our services, no personal information has been accessed."

The intrusion was identified as DDoS or distributed denial-of-service attack.

According to Digital Attack Map, DDoS is "attack is an attempt to make an online service unavailable by overwhelming it with traffic from multiple sources. They target a wide variety of important resources, from banks to news websites, and present a major challenge to making sure people can publish and access important information."

The usual targets of this kind of assault are high-profile web servers of banks, credit card payment gateways, but recently also popular gaming networks like PlayStation Network.

A Twitter user named LizardSquad claimed responsibility of the attack and posted the statement:

"Sony, yet another large company, but they aren't spending the waves of cash they obtain on their customers' (PlayStation Network) service. End the greed," the tweet stated.

The same account declared that there were explosives planted on American Airlines plane carrying Sony Entertainment President John Smedley.

Smedley confirmed in his Twitter status that his flight was diverted.

Casey Norton of American Airlines said that Flight 362 from Dallas/Fort Worth to San Diego was diverted to Phoenix due to security issues, but did not disclose other details.

After checking in on passengers and crew members of the said flight, they were allowed to proceed to its destination, and landed safely in San Diego.