Updated

A boy who said on the Internet that he planned to bomb his high school was turned in by the 16-year-old daughter of a university police officer who heads a cyber crimes unit, authorities said.

Authorities credited Celia McGinty (search) of Moscow, Idaho, with foiling a plot to bomb Chippewa Valley High School (search) outside Detroit.

Police said a search of 17-year-old Andrew Osantowski's (search) home last week turned up instructions for making a bomb and videotapes of him with assault weapons. Osantowski was arrested Thursday; his father and a family friend also were charged.

McGinty met Osantowski online in a music chat room three weeks ago. She said Monday on ABC's "Good Morning America" that the boy — who started at Chippewa Valley High School on Aug. 31 — was very specific about how he would take revenge on teachers and schoolmates.

"He told me where he had his weapons," she said. "He gave me his name and address. Who would do that?"

Osantowski has been jailed on more than $1 million bond on 10 felony charges, including threatening an act of terrorism, and could face up to 20 years in prison. A judge entered a plea of not guilty on his behalf.

Police said Osantowski told McGinty about plans for violent revenge at the school, including plans to kill a police liaison officer, and she alerted her father, George, who heads the cyber crime unit for the Washington State University police.

"She realized when the conversation turned bad, it was time to pass that information on," George McGinty said.

Besides the bomb instructions and videotapes, police Friday displayed other items they said were found in the home, including weapons and ammunition, Nazi flags and books about white supremacy and Adolf Hitler.

Marvin Osantowski, 52, the boy's father, was charged with concealing stolen firearms and pleaded not guilty. Bond was set at $500,000.

Dominic Queentry, 33, a family friend, provided the teen with bomb-making instructions, police said. Investigators said they found explosives, weapons and drugs in his home. He was charged with possessing explosives and other counts and pleaded not guilty. Bond was set at $100,000.

Ralph Roberts, whose daughter attends Chippewa Valley High, said he planned to fly McGinty and her father to Michigan to be honored at the school.

"In my opinion, she's a hero because she's being raised by a hero," said Roberts.

McGinty said he and his daughter would probably accept the invitation so Celia can talk to students about the importance of detecting and reporting Internet threats.