Metallica is helping law enforcement authorities try to catch the killer of a Virginia Tech student who disappeared nearly three years ago after one of the heavy metal band's concerts.

Lead singer James Hetfield recorded a public service video, posted on YouTube, urging people to come forward with tips.

"Remember, any information - no matter how small you might think it is - could be that crucial piece investigators need to help solve the case," Hetfield said in the video, which is also posted on an FBI website dedicated to the case.

The video is part of a revived effort by law enforcement to find the man who killed Morgan Harrington, a 20-year-old aspiring teacher. Harrington disappeared Oct. 17, 2009, during a Metallica concert on the University of Virginia campus. Her body was found in January 2010 at a farm in Albemarle County, not too far away.

The FBI recently released a revised sketch of the suspect who has also been linked to a 2005 sexual assault case in Fairfax City some two hours north. In that case, the suspect grabbed a woman and dragged her to a pool and park area and sexually assaulted her.

Harrington had gone to a Metallica concert at the John Paul Jones Arena in Charlottesville when she got separated from her friends, who believe she stepped outside for a cigarette.

Surveillance cameras at the concert caught Harrington getting turned away from several entrances as she tried to return to the concert. Later, witnesses told police they saw someone matching her description in a nearby grassy parking lot, and then walking on an adjacent road.

The morning after the concert, Harrington's purse and cell phone were found in that grassy field and later, her parents Dan and Gil Harrington, called police to report her missing.

Gil Harrington told The Associated Press that she and her husband are hopeful the new publicity effort will lead to an arrest.

"Our big motivation now is to catch this man and help save the next girl because he is a predator at the top of his game," Harrington said Wednesday.

The Harrington family is offering a $100,000 reward for information leading to an arrest in the case. Metallica has also offering an additional $50,000, bringing the total up to $150,000.

"To have abduction, rape and murder of your child is an obscenity. It is an abomination," Gil Harrington told AP. "The band reacted to that right away. It was a matter of days before James Hetfield was on the phone to Dan saying, 'As a father, I am outraged.'"