French, Belgian and Dutch police have launched investigations into minor explosions which struck IKEA stores in each country yesterday in what appears to have been a co-ordinated attack.
No-one was seriously hurt in the blasts at the world's biggest furniture retailer, although two workers in Belgium suffered minor injuries.
Rigged alarm clocks blew up in IKEA stores in Ghent, Belgium and Lille, France, and there was an explosion in a bin outside the IKEA store in Eindhoven, the Netherlands.
The alarm clocks were linked to small amounts of gunpowder, and prosecutors said they did not think that the bombers had intended to cause significant injury.
'Federal police with dogs did a sweep of other stores but there was nothing suspect that was found,' An Schoonjans, a Ghent prosecutor, told Reuters.
The affected IKEA stores in Belgium, France and the Netherlands all opened as usual on Tuesday.
A spokeswoman for IKEA, a global brand associated with for low-price, self-assembly flat-packed furniture, said there had been no warning before the attacks.
IKEA risk manager Edwin Gaasenbeek told Dutch news agency ANP there was no reason for extra security measures at the company, owned by a foundation controlled by Swedish founder Ingvar Kamprad.
'Of course, it has happened before. But we do not consider it as blackmail or extortion,' Gaasenbeek was quoted as saying.
Two Polish men were jailed in 2004 for planting bombs at two Dutch Ikea stores in 2002 and trying to extort €250,000 from the Swedish furniture chain.
In 2009, there was a threat to blow up several Amsterdam stores, including an IKEA outlet, and seven people were arrested but it turned out to be a hoax and the people were released.