Updated

A 15-year-old boy who had shown strong interest in the Columbine (search) school shootings has been arrested for allegedly plotting to blow up his high school, authorities said Thursday.

The high school sophomore had assembled bomb-making materials including gunpowder and fuses, and a search of his home showed that the boy was seemingly fascinated with the Columbine massacre, officials said. Authorities found downloaded autopsy reports on Columbine shooters Dylan Klebold (search) and Eric Harris (search), crime scene photos and pictures of the weapons.

The student talked about his plans with other students, who alerted officials at his high school outside Buffalo.

"He had stated an intent to blow up the school," District Attorney Frank Clark said. "He had purchased the gunpowder, he had primers, he had the pipes which had already been bored out, he had the ball bearings."

The boy also wrote an essay for his English class this year suggesting Klebold and Harris were rebelling against an oppressive atmosphere, authorities said.

"Obviously, I'm concerned. I knew the student," said Geoffrey Hicks, superintendent of the 3,900-student district.

The student's name was withheld because of his age. He is charged in Family Court as a juvenile and is not eligible for prosecution as an adult, Clark said. He could face up to a year in a residential treatment center if found guilty.

The teen told investigators that he was planning the attack for his senior year and that the intent was not to hurt anyone, but to show police they were not adequately protecting people, authorities said.

But the prosecutor expressed doubts about the student's intentions.

"He had all the makings of the bomb as of last week, so his professed intent not to do it for two years rings a little hollow," Clark said. As for not hurting anyone, "it's a rather incongruous explanation," he said.

"It wasn't as though he had only talked about it," Clark said. "He had actually started to purchase materials and construct materials, so it was a little scary."

The boy's arrest came two days after a shooting in Minnesota in which a 16-year-old boy killed nine people, including seven at the high school, before killing himself.