Part of Vinas' case is key information in the ongoing trial of Malika El Aroud, the widow of an al Qaeda suicide bomber who killed Northern Alliance commander Ahmed Shah Massoud two days before the Sept. 11, 2001, attacks.
Aroud was arrested last December in an alleged terrorism plot that was disrupted just before an E.U. summit. Although a total of 14 individuals were arrested in that case, only six defendants were deemed to be held for trial.
A decision on how their cases will play out could come as early as next week; information provided by Vinas is deemed a critical component, according to officials briefed on the matter.