UPDATE, 16:49 GMT: Sony has admitted that its engineers are investigating the possibility that the PSN network has been hacked. Full story here.
An outage of the Sony PlayStation Network today sparked rumours that the online gaming service may have been the subject of a DDoS attack by 'hacktivist' collective Anonymous.
The disruption has hit at a particularly bad time for Sony, coming on the day that cross-platform gaming hit Portal 2 is released for the company's PlayStation 3 console.
Users across Europe and in the US have reported problems logging into the PlayStation Network. The official EU PlayStation blog this morning informed users this was due to maintenance work, in a post on Twitter, and said updates on its progress would be available here.
But with no maintenance having been announced in advance, speculation is rife about the cause of the downtime.
Loose-knit collective Anonymous launched a string of DDoS attacks against high-profile Sony sites earlier this month under the banner 'OpSony'. The action was in retaliation for Sony's legal pursuit of hackers who opened up the its PlayStation 3 console to third-party firmware.
Targets included the PlayStation Network, but Anonymous soon announced it had "temporarily suspended" action against PSN, saying that it wanted to punish Sony, not its customers.
This morning's outage raised fears that the attacks had been renewed.
"Something tells me this was unplanned maintenance", wrote one user on PSN's community forums.
Another said: "Something is seriously wrong with PSN since those attacks. I'd rather Sony get to the bottom of it with what ever means they need to."
No announcements about today's outage have yet been made via the usual Anonymous news channels.
Last week, OpSony threatened the firm with "the biggest attack you have ever witnessed", but promised to fight on after planned protests at Sony high-street stores worldwide failed to materialise.
More news as soon as we have it.