Both tweets have now been removed, which suggests that perhaps the claims were a hoax.
To further muddy the waters, a Sony employee, Shane Bettenhausen of the business development unit, tweeted that the claims were "totally fake."
However, his tweet has now subsequently been removed also.
The Great Hack of 2011
The previous PlayStation Network hack in 2011 put the online gaming portal out of commission for around six weeks and caused Sony to rethink its entire security
It compromised the personal data, including, it is thought, the credit card details, of up to 100m members.
The saga caused huge damage to the reputation of Sony's PlayStation brand and sparked a long summer of hacks to popular gaming companies like Nintendo and Codemasters.
Sony blamed Anonymous, while Anonymous denied it was responsible. The hack was eventually attributed to the offshoot group LulzSec.
Another hit would be a huge blow to Sony. We'll let you know when there's official word either way, but it appears that this may be a false alarm.