A major cyberattack reportedly by pro-Isis hackers paralysed the systems of French television network TV5Monde.
Apart from halting broadcasting operations, the attackers took control of the network's websites and Facebook page.
Following a three-hour long blackout, the Paris-based broadcaster resumed partial operations.
A message posted on the network's Facebook page read: "Soldiers of France, stay away from the Islamic State! You have the chance to save your families, take advantage of it. The CyberCaliphate continues its cyberjihad against the enemies of Islamic State [Isis]."
TV5Monde's director general Yves Bigot admitted the network's systems were "severely damaged" by an "extremely powerful cyber-attack".
"We are no longer able to broadcast any of our channels. Our websites and social media sites are no longer under our control and are all displaying claims of responsibility by Islamic State," said Bigot.
The hackers also allegedly posted details of family members of French soldiers who are involved in the anti-IS operations in Iraq and Syria.
Accusing French President Francois Hollande of committing an "unforgivable mistake", the cyber-attackers said French cooperation with the US-led military campaign serves "no purpose".