Three middle school students were charged Friday with plotting to kill their classmates and themselves, police said.

Two boys and a girl, all 13, were taken into custody shortly after the plan was discovered on March 5. Their mental health was evaluated before they were transferred Friday to a juvenile detention center, said Volusia County sheriff's spokesman Gary Davidson.

Investigators said in a news release the ringleader had exchanged instant messages with a DeLand Middle School classmate, saying "I will kill every person I see. ... Everyone will pay for what they did to me."

The student, who claimed he was being teased and picked on by other students, threatened to lock the cafeteria doors during lunch and shoot everyone in sight, according a sheriff's office news release.

"They will all die along with me," the student wrote, according to the release. "The massacre will happen soon."

The classmate was so disturbed she sent the messages to a family member, who contacted the sheriff's office. Deputies tracked down the student at his home hours later and took him into custody.

Other students at the middle school also told investigators they heard two seventh-graders openly discussing the plot with the ringleader, police said. They were later taken into custody as well.

The ringleader had asked another classmate whether he could get a gun, but the classmate said he couldn't, according to the sheriff's office. The classmate wasn't among those charged.

On the ringleader's MySpace page, he expressed admiration for the teenagers responsible for the Columbine High School killing spree, according to police.

A detention center official would not say whether any of the students had attorneys.