A 13-year-old girl who had been missing from her Pittsburgh home since New Year's Day was found yesterday tied to a bed in a Herndon town house after federal officials received a tip generated from the Internet.

FBI agents believe Alicia Kozakiewicz had an Internet correspondence with Scott Tyree, 38, who rented the town house in the 700 block of Hemlock Court.

Tyree apparently picked her up Tuesday in Pennsylvania and brought her to his home, authorities said.

Jack Shea, special agent in charge of the FBI's Pittsburgh field office, said Alicia was found "restrained" at Tyree's home about 3 p.m. She was taken to Inova Fairfax Hospital for evaluation, but the FBI would not say whether she was injured.

She was placed with Fairfax County Child Protective Services until her parents could arrive. Shea said that Alicia's parents were in Pittsburgh last night and that the FBI was trying to arrange for them to come to Virginia today. Tyree is expected to appear before a U.S. magistrate judge in Alexandria on Monday on a charge of transportation of a minor for the purposes of engaging in illegal sexual conduct, federal officials said.

The FBI credited a tipster, as well as the Internet service provider Yahoo, with helping to rescue the girl.

Shea said a Florida man called the FBI's Tampa office Thursday night after chatting over the Internet with a man he knew as Scott. Scott said that he had been in contact with a teenage girl and that he had gone to Pittsburgh to pick her up, the man told the FBI. The man said Scott even produced an Internet picture of the girl.

The Florida man compared the picture to one he found on the Pittsburgh Post-Gazette newspaper's Web site and believed it was the same girl the FBI and Pittsburgh police had been searching for, Shea said.

The FBI tracked Tyree through Yahoo, which provided his address. He was at work at a Herndon computer company when FBI agents raided his home. He was arrested at the computer company.

The Post-Gazette said Alicia is an aspiring model. She was eating a traditional New Year's dinner of pork and sauerkraut with her family and disappeared as they cleared the dishes for dessert, the paper said. She did not take her coat or any money, leaving the family frantic.

Mary Kozakiewicz told the newspaper that her daughter, an eighth-grader at Carlynton Junior High School, is an average student who loves writing and composed poems for her parents for Christmas.

Tyree has lived in the Herndon three-bedroom town house for six years, said his landlord, George Murphy. He paid $1,000 a month, usually in cash, Murphy said.

"There was no activity or anything that would alert you to the fact that something weird was going on," he said.

Tyree's mother, Erma, of Keyser, W.Va., said last night she was unaware of the charges but insisted there had to be some kind of mistake.

"That can't be my son," she said. "I know that this is the kind of thing mothers say, but this has got to be a mix-up."

Tyree said her son's 12-year-old daughter had been visiting him and returned to his ex-wife's home in California on New Year's Day. The ex-wife could not be reached last night.

"He's a very good father, and he's always been a good son, and I don't believe this for one minute," Erma Tyree said. "He's always been very hard-working, a good boy. He doesn't drink. He doesn't smoke. It's a big shock."

On Wednesday night, investigators were trying to analyze Alicia's computer for clues to who might have been talking with her over the Internet, Shea said.

When the tip came from Florida, "it helped us significantly by moving us a couple of steps ahead quicker," Shea said.

Neighbors said Tyree generally kept to himself.

Murphy said he moved in by himself, lived with a woman for a few years but lives by himself again now.

One neighbor, who declined to give her name, said curtains that Tyree normally kept open had been closed in recent days.

Tyree told the neighbors he was going to spend New Year's Eve at an Alcoholics Anonymous party. The neighbors said they had not heard or seen anything suspicious since then, though they had noticed road salt on Tyree's car since Wednesday.

"That's how life is today," said one woman who lives nearby. "You've got to keep looking over your shoulder."

Van A. Harp, the head of the FBI's Washington field office, said at a news conference last night that parents should be vigilant about monitoring their children's Internet activity.

"Make sure you are aware of what your children are doing on the Internet," Harp said. "There are sexual predators, not surfing, but trolling the Internet."

Staff writers Leef Smith and Brooke A. Masters and researcher Bobbye Pratt contributed to this report.

Authorities say they think Scott Tyree, 38, had an Internet relationship with 13-year-old Alicia Kozakiewicz. A tip stemming from another Internet chat led to Alicia's freedom and Tyree's arrest.