A week after she inexplicably vanished from Metallica's Oct. 17 concert, there is still no sign of Morgan Harrington, a blue-eyed blond 20-year-old Virginia Tech student, after an exhaustive ground and aerial search and tips phoned in from hundreds of sources of varying credibility.

Harrington, whose case has drawn national attention, was last seen in a Pantera shirt, a black skirt and black boots. She went to the concert with friends, but, after going to use the bathroom, somehow found herself outside the venue, where there is a no re-entry policy. On Oct. 23, the Federal Bureau of Investigation joined the investigation, which is being handled as a criminal matter. While this could mean the scope of the investigation is spreading beyond Virginia's borders, the FBI, according to reports, will help in tracking down tips from around the country.

A task force investigating the killings of two Virginia Tech students back in August has ruled out any connection between Harrington and the couple who were killed in Jefferson National Forest.

According to one report, a grandmother from the Richmond, Va., area who claims she was in the parking lot of the site of the Metallica concert, the John Paul Jones Arena, that very evening believes she saw Harrington, and her story is disturbing.

She claims a young woman and a young man were physically struggling with one another, and that the young woman looked a lot like Morgan. The grandmother has asked to remain anonymous.

The woman called police Monday night, after seeing Harrington's picture on the news. She says the fight happened behind her car, which was parked outside the arena while Metallica were still on stage. The woman was there to pick up her son and grandson from the concert. Then, she claims she heard a loud noise.

"I heard them being very loud and it sounded like maybe like she got smacked or something," the grandmother says. "The two people were in, like, a hand lock; she had her hands on his arm and he had his hands on her arm, pushing back and forth."

She says the girl then started walking back toward the arena and the young man headed for the road, but later, ran back to the girl. She says it appeared the two knew each other, and she only had a vague description of the young man she saw.

Meanwhile, police shut down access to the Comfort Inn motel at I-64 and Route 250 in Charlottesville, Va., on Oct. 24, and confirmed they were looking for Harrington. Police were looking into a tip they'd received about the parking lot in front of the motel, not the building itself.

A $100,000 reward for information leading to Harrington's whereabouts is being offered. You can go to FindMorgan.com for more information.

Metallica issued a statement earlier this week, saying that they "are deeply concerned about the disappearance of Morgan Dana Harrington. She was not carrying I.D. or a cell phone. Morgan was separated from her friends shortly before 9 PM at the venue, and police have been searching the area since Monday. We encourage anyone who has any information regarding Morgan's disappearance to please come forward. Our thoughts are with Morgan and her family for her safe return."