Operations of French-language TV channel TV5 Monde were severely disrupted late Wednesday (French time) by hackers claiming to be part of terror group Islamic State.

TV5 lost control of its TV station, website and social media accounts.

The company’s director general Yves Bigot, said it had been “severely damaged” by the “unprecedented attack.”

The hackers posted images of a masked man on some pages and warnings on TV5’s Facebook account. They also posted ID cards of French military personnel claimed to be involved in anti-IS operations. “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,” said one message.

The TV operations, which are syndicated worldwide, were back on air within three hours. But at 5am French time, more than 8 hours after the attack began, some of its website pages were still unavailable “due to maintenance”.

The channel is owned by a coalition of French-language broadcasters in France, Europe and Canada, with French state-owned group France Televisions its largest shareholder, with 49%.

The French government has been an active supporter of the U.S.’s military campaign.

In January the Twitter and YouTube accounts of the U.S. military command were also hacked by claimed IS supporters.