WPP's website is down after a huge cyber attack.
The advertising giant has confirmed that a number of its companies have been affected by a hack that initially hit Ukraine, but has now started spreading to other countries around the world, including Spain and India.
How the attack began is not yet clear, but there are fears that it could be like the enormous WannaCry attack that locked staff out of NHS computers in May.
"IT systems in several WPP companies have been affected by a suspected cyber attack," the WPP said in a statement.
"We are assessing the situation, taking appropriate measures and will update as soon as possible."
The company's website isn't working at the time of writing, though it isn't clear if the WPP took it down itself or if the attackers knocked it offline.
It currently displays a message reading,"The WPP web site is currently unavailable due to important routine maintenance normal service will resume shortly.
"We apologise for any inconvenience this may cause."
WPP owns a huge number of advertising and PR firms, including Ogilvy, MediaCom and Burson-Marsteller.
Ransomware known as 'Petya' is believed to be to blame, and has also targeted Ukraine’s national bank, state power company and largest airport.
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