The potentially lethal nuclear enrichment material that Bulgarian customs prevented from crossing into Romania is linked to Iran's nuclear quest, the Sunday Herald reported, citing Romanian sources.

"The sources could not give the intended final destination of the consignment, but the "working hypothesis" of Balkan police forces is that "it is linked to Iran's nuclear quest". Then again, there are always al-Qaeda armourers keen to buy dirty bomb material."

According to the reports an Arab-dominated Bucharest mafia was the inter mediary in the hafnium deal.

A week ago Bulgaria's police in the northeastern Danube city Russe nabbed 3.5kg of hafnium, a material that could be used in the manufacture of radioactive "dirty bombs".

The article raises a number of questions over the releasing of the smuggler's Romanian companions after the Bulgarian driver of the smugglers' car admitted that the hafnium consignment was his property.

"The sudden and unconditional freeing of the smuggler's Romanian companions raises justifiable fears about the financial clout of the mafias apparently involved, and the legendary corruptibility of Balkan police forces. Bulgaria, like Romania, is hoping to join the EU in 2007, but corruption is seen as one of the main stumbling blocks in its path."