Defense attorneys presented no evidence and called no witnesses before resting Tuesday in the federal trial of a Saudi man accused of gathering materials to make a bomb.

The stunning move came after prosecutors rested their case against Khalid Ali-M Aldawsari. Closing arguments are scheduled for Wednesday morning in Amarillo.

Aldawsari, a former Texas Tech chemical engineering student, is charged with attempted use of a weapon of mass destruction. Prosecutors accused him of having a list of potential targets, including former President George W. Bush's home in Dallas. The 22-year-old defendant could be sentenced to up to life in prison and fined up to $250,000 if convicted.

During an FBI agent's testimony Tuesday, authorities showed videos they said they found on a flash drive in Aldawsari's apartment. One showed a masked man speaking in Arabic about the chemicals needed to create picric acid, an explosive. Other agents have testified that Aldawsari sought -- and failed -- to obtain one of the three chemicals, phenol.