It followed a sting operation by the FBI in a case widely hailed by US authorities at the time as a victory in the then so-called war on terror.

The men's arrests had been announced in Washington at a news conference by Alberto Gonzalez, the then US attorney-general.

'Aspirational' plot

At the time, the authorities said the plot was "aspirational rather than operational", and that the men posed no real threat because they had neither al-Qaeda contacts nor the means of carrying out attacks.

Prosecution lawyers said the men had taken photos of possible targets and scouted out Miami's FBI headquarters and a courthouse, surveying entry ramps, surveillance cameras and guardhouses.

According to the prosecution, Batiste suggested an attack on the Sears Tower, America's tallest skyscraper.

However, the men's defence lawyers said they had been goaded into the plot with the help of informants who posed as Middle Eastern contacts and said the men had only gone along with the plot in an attempt to extract money from the informants.

The men are due to be sentenced on July 27.