This morning 350,000 Facebook users vanished into a black hole. Facebook banned Popolo Viola’s page (Purple People), the organisers of the biggest anti-Berlusconi protest, only to reverse its decision this afternoon.

One of the pages administrators expressed his suspicions about the page’s closure, noting it happened “just as the Purple People was organising the protests tomorrow, December 14, during the vote of confidence to [Italian Prime Minister Silvio) Berlusconi,”

The Purple People movement, born and bred on the web, has attracted hundreds of thousands of keen followers. After the first No Berlusconi Day protest, which took place just over a year ago, its popularity  spread. Now the grass-roots organisation has a huge network of local organisations in Italy and abroad (there is even a London branch).

The reasons for the Facebook blackout are still unknown.  The page’s administrators say “We are waiting to get to know the motivations of what happened. We will keep you informed about the developments”.

The activists themselves speculated that the outage could be linked to tomorrow’s vote of confidence in the Italian parliament. A vote that  could cost Berlusconi his presidency. Last week, leaked Wikileaks cables revealed that Berlusconi was worried about the activists, whom he defined “extremists to be kept under control”. Although others, including a reporter at Fatto Quotidiano newspaper, suggested that internal quarrels within the Purple People caused the temporary suspension.