The large and influential French TV network TV5Monde was taken off the air and its online presence was hijacked by a group calling itself the Cyber Caliphate. Hours after the attack began, the network was still unable to produce live programming.

The attack by what are being called cyber jihadists began at 10 p.m. in Paris on Wednesday, when screens that would normally show TV5Monde went blank, with normal programming replaced by a message: "Je suIS IS."

The hackers also showed what it claimed were ID cards of relatives of French soldiers who are involved in operations against the self-proclaimed Islamic State. A message urged the soldiers not to join the fight.

In a video message posted to Facebook, network director general Yves Bigot called it "a very powerful cyber attack." Within several hours, TV5Monde had regained control, if not the use, of most of its systems; its website remained offline until nearly 1:30 p.m. (local time) Thursday.

From Paris, Jake Cigainero reports for our Newscast unit:

"Prime Minister Manuel Valls denounced the hack on Twitter, calling it an unacceptable attack on freedom of information and expression."The same day, the network launched a new lifestyle channel about 'the art of French living.' The 11-channel network broadcasts in more than 200 countries and territories, including the Middle East and North Africa."Bigot said it could be days before the network schedule returns to normal."

It's not yet known what actual ties, if any, the hackers might have to ISIS. News channel France 24 says that after its expert on jihadists, Wassim Nasr, read mistake-riddled messages in Arabic that were posted by the hackers on Facebook, he concluded "the authors are not Arabic."

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