Two 17-year-olds suspected of plotting a shooting spree at their school were fascinated with the mass killings at Columbine High School and had homemade bombs and weapons at their homes, investigators said Friday.

The boys were arrested Thursday at East High School after a student went to an associate principal. A detective said Friday that one boy wanted to enact the plan Thursday but the other talked him out of it.

"If someone hadn't come forward, we'd be talking about funerals instead of charges," said Brown County District Attorney John Zakowski.

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William C. Cornell and Shawn R. Sturtz were arrested for suspicion of conspiracy to commit first-degree intentional homicide and conspiracy to commit arson. Zakowski said he planned to file charges next Thursday.

Court Commissioner Jane Sequin ordered each teen jailed on $500,000 bond Friday. Police Detective Tom Molitor testified that both teens, who are seniors, told police that they had been plotting the massacre for several years.

They planned to set off bombs near bathrooms, light the exits on fire with jelled gasoline so no one could escape and shoot people they had problems with, Molitor said.

Police found nine rifles and shotguns, a handgun, about 20 "crudely made" explosive devices, camouflage clothing, gas masks, two-way radios and hundreds of rounds of ammunition at Cornell's house, Police Capt. Lisa Sterr said. She said Cornell had made several of the improvised explosive devices about two months ago.

At Sturtz's home, police found knives and ammunition, Sterr said.

Police said they also found mannequin heads that appeared to have been used for target practice, and suicide notes.

No dangerous materials were found at the school, Sterr said.

The two teens had long been fascinated by the April 1999 Columbine massacre in Littleton, Colo., in which two students armed with guns, knives and bombs killed 12 classmates and a teacher before killing themselves, Sterr said.

In Montreal on Wednesday, an attacker killed a student at Dawson College and wounded 20 others before killing himself. Kimveer Gill, 25, had dressed in a black trench coat like the Columbine shooters, posted online photos of himself with weapons and said he liked to play an Internet role game about the Columbine killings.

Sturtz was described as being obsessed with pain and death, and both he and Cornell had been described as being depressed and hating school, according to Sterr.

Sturtz had also just lost an Internet relationship with a girl, Sterr said.

"Sturtz was very upset about this and became extremely enraged and (Wednesday) talked of soon attacking the school like Columbine," Sterr said.

Molitor said the two just needed a triggering event to pull off their plan. "They were one bad day away from something happening," he said.

Molitor said in the court hearing that Sturtz wanted to enact the plan on Thursday but Cornell talked him out of it.

A student, Jason Burdick, 18, who said he considered both teens friends, described Sturtz as a "teddy bear" and a shy, quite kid.

"He was nice to get along with. No fights or whatever," he said. "But he, like, turned."

Burdick said Sturtz started watching documentaries and other programs about Columbine.

"I think that is what kind of turned him," he said. "I didn't think anything of it. He just kind of joked around with it. You know, just talking."

Burdick said he played war games once with Sturtz with BB guns.

"I went over there one night and we had like little battles," he said. "It was just like a fun little sport."

Felicia LaPere, 17, said Sturtz had a darker side and was into Goth culture.

"But there was nothing suspicious about him that you would think he would try to do something like this," she said.