Around 50 firemen put out the blazes which broke out within half an hour of each other at the restaurants in Avrainville, Les Ulis and Ville du Bois. Two of the establishments were completely gutted.

No clues were immediately found as to the cause of the simultaneous blazes.

Late last year trading of shares in the Buffalo Grill chain was suspended for three weeks owing to a scandal over alleged secret imports and use of banned British beef.

Trading was suspended on December 18 amid allegations the company illegally imported British beef and served it to customers at a time when it was banned due to fears of "mad cow" disease.

French authorities launched criminal investigations against several of the group's senior executives in December after finding that two people who died of Creutzfeldt-Jakob disease -- the human variant of mad cow disease -- had eaten at Buffalo Grill outlets.

SPACE.WIRE