Ask PlayStation, the official PlayStation Network support Twitter, has confirmed the online service for the Playstation 3 and PSP consoles is "currently undergoing sporadic maintenance."
"Access to the PSN may be interrupted throughout the day. We apologize for any inconvenience."
No ETA has been given on when normal service will resume.
Just a few hours beforehand, the mysterious hacker group Anonymous threatened Sony over its continuing legal actions against PlayStation 3 hackers GeoHot and Graf_Chokolo.
Sony has given no indication that the outage is connected to external attack.