The official Winter Olympics website offline after being hit by a cyber-attack, confirmed officials.
The site was affected, shortly before the start of the opening ceremony in Pyeongchang, South Korea.
TV and internet systems, which interrupted the Games were, when operations were restored about 12 hours later.
But a spokesman said that the International Olympic Committee would not comment on who would be behind the incident.
“Maintaining safe operations is our goal,” said Mark Adams.
He added that the Problem be treated, but that he was not aware who had carried out the attack.Russia responds
Before the Games, some cyber-security experts, the concern expressed that countries like Russia and North Korea could try to use the target of the event.
But the Russian foreign Ministry has denied rumors that Russian hackers were involved.
“We know that the Western media are planning a pseudo-investigations “on the topic of” Russian fingerprints ” in the Hacker attacks on information resources around the hosting of the Olympic Winter games in the Republic of Korea,” the foreign Ministry said.
“Of course, no evidence the world will be presented.”
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It fears for the months that the games and the audience the target of cyber-attacks.
Earlier this month, the U.S. Department of Homeland Security has a warning for travelers published.
“At high-profile events, cyber-activists might take advantage of the large audience to spread their message”, it said.
“There is also the possibility of the mobile phone or other communication is monitored.”
The Pyeongchang games are certainly not the first to be targeted by hackers.
In January, Konstantinos Karagiannis, BT’s chief technology officer for security, consulting, tweeted that during the Olympic games 2012 in London he and his team “fought back quite a cyber-attack”.