(CBS) CHARLOTTESVILLE, Va. - The parents of a 20-year-old Virginia Tech student who disappeared outside a Metallica concert say they fear their daughter is the victim of foul play but hope for her return.

The rock band has posted photos of Morgan Dana Harrington of Roanoke on its Web site.

According to a notice on another Web site for the missing student:

The Harrington family is offering a $100,000 reward for the safe return of their daughter, Morgan Harrington, or information leading to the arrest and conviction of the person or persons responsible for Morgan Harrington's disappearance.

The Band Metallica is also adding an additional $50,000 to the reward bringing it to $150,000 for Morgan's safe return or information leading to the arrest and conviction of the person or persons responsible for Morgan's disappearance.

Harrington's parents said Tuesday on NBC's "Today" they are devoting all their energies to finding Morgan, who was last seen Oct. 17 outside a University of Virginia arena in Charlottesville.

Dan Harrington called his daughter's disappearance "a parent's worst nightmare." Gil Harrington said she is worried that Morgan was the victim of foul play.

Police have said they are treating the search as a criminal investigation.

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