ALEXANDRIA, Va. (AP) -- A plea hearing has been scheduled for a naturalized citizen from Pakistan charged with joining what he thought was an al-Qaida plot to bomb the D.C. region's Metrorail system.

Farooque Ahmed of Ashburn, Va., is expected to enter a guilty plea Monday in federal court in Alexandria. The exact charges to which Ahmed would plead are unclear. He was initially charged with conspiring to provide material support to al-Qaida and collecting information for a terrorist attack on a transit facility.

Authorities say Ahmed plotted with people who turned out to be part of a government sting. He allegedly took video of northern Virginia subway stations and suggested using rolling suitcases rather than backpacks to kill as many people as possible.

A call to Ahmed's lawyer was not immediately returned Friday.

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