( CNN ) -- Police in Poland have arrested two men in connection with explosions at Ikea stores in several European countries , they said Saturday . The two men , both age 39 , are accused of trying to force Ikea to pay a ransom of 6 million euros ( U.S. $ 8 million ) . They were arrested after a joint operation involving several hundred officers from Poland 's Central Investigation Bureau and investigators from other countries , police said in a statement . There were eight explosions of increasing strength between May and early September , at large stores in France , Belgium , Holland , Germany and the Czech Republic , police said . Initially the explosions were treated as individual cases in the countries where they occurred , but police now believe the plot was orchestrated from Poland , the statement said . The suspects made use of technology and traveled large distances to try to avoid detection in Poland , it added . The men have been accused of racketeering and extortion offenses , as well as endangering people 's lives . One of the suspects , identified as Adam K. , has no previous criminal record , is fluent in four languages and previously worked as a manager at several large corporations , giving him technical expertise , police said . The second suspect , identified as Nicholas G. , has a record of past drug offenses , police said . CNN 's Per Nyberg contributed to this report .
Polish police say the men were trying to extort 6 million euros from them . The attacks occurred at Ikea and in several countries this year . Police say the men tried hard to cover their tracks in Poland .