CARY, Ill. - An 18-year-old high school student faces disorderly conduct charges for writing an essay that authorities described as violent and disturbing.

Allen Lee, a senior at Cary-Grove High School, was arrested near his northern Illinois home after penning the in-class writing assignment Monday. The assignment had been to use poetic conventions to express ideas and emotions.

"At the very last sentence, I said that this teacher's method of teaching could lead to a school shooting," Lee said Wednesday. He said he'd intended the entire essay as a joke.

After reading the essay, his teacher alerted the school's principal. District officials then reported it to the police.

"The writing assignment depicted violence, was disturbing and inappropriate, but did not contain any specific locations or names," Cary police Chief Ron Delelio said.

Albert Lee said his son was not suspended or expelled but is attending classes somewhere else for the time being.

"I understand what happened recently at Virginia Tech," said Albert Lee, referencing last week's shooting of 32 students by gunman Seung-Hui Cho. "I understand the situation."

But he also defended his son as a straight-A student who was following instructions for the assignment.

Allen Lee has been removed from the school and faces disciplinary action, said Jeff Puma, a District 155 spokesman.

Police have declined to release a copy of the essay.

"It raised some flags," Puma said. "I think, in this case, the teacher chose to err on the side of caution and, I think, rightly so."

Ed Yohnka, spokesman for the American Civil Liberties Union of Illinois, said an essay done for homework would ordinarily be "protected speech."

"He turned it in to a teacher. He didn't post it online," he said. "It's not a communication between him and the broader world."

On Wednesday, students at the school showed support for Lee with a petition drive to let him back into school.

Lee, who was arrested Tuesday, posted $75 bond.

He is scheduled to appear in court June 18.