The Madrid office of Deloitte was this week destroyed by a massive high-rise fire.
The Big Four firm occupied 20 floors of the 32-storey Windsor Building, which caught fire on the night of Saturday 13 February. Firefighters suggested a short circuit caused the blaze, which damaged the structure so badly that engineers feared it would collapse.
Around 1,000 Deloitte staff worked in the building, but so far there have been no reports of casualties.
A Deloitte spokesman said that the firm's contingency plans were being put in motion with help from the Deloitte Touche Tohmatsu headquarters in New York. Deloitte already has experience of dealing with such situations as its World Trade Center office was destroyed in the 9 September 2001 terrorist attack on New York.
IT systems were being backed up and communications from the Madrid base were being redirected to other sites.
"Client service operations will not be impacted by this event," the firm said as most employees resumed work on the Monday morning.
Deloitte has already researched new locations and expected to find a suitable base within days.
"Deloitte thanks the unconditional support and collaboration from its clients, suppliers and professionals, which is helping the Firm to normalise its activity," it said.
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