A cyber-attack has hit the major facilities company ISS World, which has half a million employees worldwide.

ISS provides cleaning, catering, security and other services to companies in the UK and elsewhere.

Its websites have been down since 17 February. And This Week in Facilities Management said 43,000 staff at London’s Canary Wharf and its Weybridge HQ, in Surrey, still had no email.

ISS said it was a “malware” attack, but declined to specify further.

The company says that many of its 500,000 global employees do not use its computers in their daily work – but the impact is affecting the whole company