(CNN) -- Four men behind what officials describe as the most serious Islamist terrorist plot ever hatched in Scandinavia were convicted of the plot Monday in a courthouse in Glostrup, just outside of Copenhagen, Denmark. Three Swedish nationals and a Tunisian resident of Sweden were found guilty of targeting Jyllands Posten, the Copenhagen-based newspaper responsible for publishing controversial cartoons of the Prophet Mohammed. The court ruled there was no doubt about their plan to attack and sentenced each of the men to 12 years in prison. Counterterrorism officials in the United States and Scandinavia believe the plot was directed by al Qaeda operatives in Pakistan.
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Each of the four is sentenced to 12 years in prison
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The four men are convicted of targeting a Danish newspaper
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Authorities say they planned a gun attack, followed by hostage executions
The cell's plans were thwarted by a joint operation of Swedish and Danish security services, which tracked the suspects in December 2010 as they drove from @placeholder to Denmark with a submachine gun, a silencer, and several dozen 9mm submachine gun cartridges, authorities say.
When they reached @placeholder, they were initially unable to find the address where they planned to sleep.