Jurors said Monday they were still deadlocked in the trial of seven men accused of plotting with al-Qaida to blow up Chicago's Sears Tower and bomb FBI offices, but a federal judge ordered the panel to continue deliberating.
U.S. District Judge Joan Lenard denied a defense request for a mistrial.
"It is your duty to agree upon a verdict if you can do so," Lenard told the jurors, who have debated the group's guilt or innocence for six days at the end of a two-month trial.
The panel of six men and six women met for three more hours Monday without concluding the case and were ordered to resume work Tuesday.
'Liberty City Seven'
Jurors sent a second note Monday to the judge indicating they were unable to reach a unanimous verdict against any of the "Liberty City Seven," named for the Miami neighborhood out of which they are accused of operating. A similar note had been issued Thursday.
Lenard has refused to publicly release the contents of the notes or allow them to be read in court.
"The trial has been expensive in time, effort, money and emotional strain to both the defense and the prosecution. If you should fail to agree upon a verdict, the case will be left open and may have to be tried again," Lenard told the jury in a set of instructions known as an Allen charge.
Federal prosecutors took no position on whether a mistrial should be declared.
Lenard did not specify how long deliberations might continue. If jurors cannot reach a verdict, the U.S. Justice Department would have to decide whether to try the case again, drop the charges or negotiate plea agreements with some or all the men.
The seven defendants each face as many as 70 years in prison if convicted on all four terrorism-related conspiracy charges. The case is built mainly on meetings between the group's leader, 33-year-old Narseal Batiste, and a pair of paid FBI informants.
There was no evidence the men had acquired any explosives or even had a definitive plan for attacks.
But some in the group took reconnaissance photos and video of the Miami FBI office and other federal buildings, and all seven took an oath of allegiance to al-Qaida and Osama bin Laden that was recorded by federal agents.
During eight days on the witness stand, Batiste testified that he was never serious about any terrorism plots and that he only went along in hopes of extorting $50,000 from one of the FBI informants, known as Brother Mohammed. Batiste also insisted that the other six men knew little or nothing about the alleged plots.