A boy accused of opening fire on classmates, killing three of them, may have been influenced by a 1995 Leonardo DiCaprio film in which the character has a dream scene in which he imagines shooting schoolmates and teachers, a prosecutor said Thursday.

"These movies are a factor. People come up with some of these ideas," said Commonwealth's Attorney Timothy Kaltenbach.He said the movie was "The Basketball Diaries," a 1995 film based on the life of Jim Carroll, a high school basketball player who turned to drugs and violence.

The film includes a dream scene, in which Carroll, played by DiCaprio, shoots classmates and a teacher, and several scenes depict religion in a negative light.

Michael Carneal is accused of opening fire on a group of fellow Heath High School students Monday morning as they wound up an informal hallway prayer session. Kaltenbach said the boy had mentioned to investigators that he had seen the school shooting scene in "The Basketball Diaries."

Three girls died and five other students were wounded.

Without going into specifics, the prosecutor said evidence has surfaced that Carneal had planned the crime for as long as a year. Kaltenbach said others possibly knew of plans for the shootings and another arrest was possible.

"If someone engaged in the planning process, they will be punished," he said.

Sheriff Frank Augustus said Wednesday that he had a "gut feeling" the shooter didn't act alone in Monday morning's shootings.

"I don't believe this boy planned this out by himself," Augustus said. "I believe there is somebody else in the background that we need to talk to. I think it's other students. I may be totally out of whack, but I just believe there's others involved."

A photo that ran in Tuesday's Deseret News with the story about the West Paducah shooting was not a picture of Michael Carneal.