Metallica has recorded a public service video as part of a law enforcement publicity blitz to try to catch a man wanted in the death of a Virginia Tech student who disappeared after leaving one of the heavy metal band's concerts.

Composite sketches of the suspect will be featured at bus shelters and on digital billboards up and down the East Coast, and a video on the Internet from lead singer James Hetfield urges people to come forward with tips and to contact police if they think they recognize the man. The FBI and Virginia State Police announced the campaign on Wednesday.

"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 says in the video, which appears on YouTube and an FBI website dedicated to the case.

Morgan Harrington, a 20-year-old aspiring teacher and Virginia Tech student, disappeared while attending an October 2009 concert in Charlottesville, Va. Her skeletal remains were discovered about three months later in a remote hay field about 10 miles from the concert venue.

Police have said Harrington became separated from friends after she left the concert early and was denied re-entry to the arena. She was last seen hitchhiking that night. Her T-shirt was found outside an apartment building near the Charlottesville auditorium, but a camera and a crystal necklace she had with her were missing.

The FBI says the suspect has also been linked through DNA to a September 2005 sexual assault in Fairfax City, Va., where a woman walking home from a grocery story reported being grabbed from behind, dragged behind a maintenance shed and attacked. Authorities this month released an enhanced composite sketch based on a description from the sexual assault victim.

"We don't know who he is so we don't know where he is," said Virginia State Police spokeswoman Corinne Geller.

Harrington's mother, Gil Harrington, said she and her husband, Dan, 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," Gil Harrington said, adding, "I have urgency as time goes on as to where he's going to strike next."

The Jefferson Area Crime Stoppers is offering $100,000 for any information leading to an arrest, and Metallica has put up a $50,000 reward.

Gil Harrington said it was an "abomination" to suffer through the murder of a child, and that the band has been supportive from the outset.

"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,'" she said.

The FBI campaign, which also includes podcasts, social media outreach and an online photo gallery, is similar to ones that have led to the arrests of former Boston mob boss James "Whitey" Bulger, and of Aaron Thomas, who is suspected in a series of sexual assaults along the East Coast.

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Online:

http://www.youtube.com/watch?v=_tkVcZB2pds&feature=plcp

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