A US federal jury has found Zacarias Moussaoui eligible for the death penalty for his involvement in the deaths of 11 September 2001.
The 12-person jury found that Moussaoui lied to the FBI following his arrest three weeks before the attacks, and the lies led to deaths in the hijacked airliner attacks that killed nearly 3,000 people.
New hearings will now be held to decide if he should be executed.
Moussaoui is the only person to be charged in a criminal court in the US over the attacks on New York and Washington.
Though he was detained before the hijacked airliner strikes, prosecutors said he lied about the planned attacks, contributing to the almost 3,000 dead.
The jury panel of nine men and three women retired to the jury room last Wednesday to decide Moussaoui's fate.
If the jury decides against a death penalty possibility, the only other possible sentence is life in jail without parole, though
prosecutors have signalled they are holding out hope for a mistrial and another shot at seeking execution, if the jury is unable to come to a unanimous conclusion.
The defense argued during the three-and-a-half week trial that government mistakes were as much to do with the failure to stop the attacks as Moussaoui's obstruction.
Moussaoui pleaded guilty last year to conspiring to fly airliners into prominent US buildings but said he was part of a
separate plot to that of 11 September, a position he reversed during his trial.
