PADUCAH, Ky. (AP) _ The teen-ager charged with murder in the slayings of three classmates inside a high school will use a mental health defense, his lawyers said Friday.

Michael Carneal, 14, was ``suffering from a diminished mental capacity at the time,'' according to defense documents.

Carneal stood next to his attorney, Charles Granner, but did not speak during the brief hearing Friday or as he was rushed from the courtroom by sheriff's deputies. He is being held at an unidentified juvenile facility elsewhere in Kentucky.

``We're in the process of hiring a psychologist,'' Granner told Judge R. Jeffrey Hines, who set a trial date of Oct. 5.

Prosecutors would not comment on the announcement by the defense, but did say in court they wanted their own psychologist to interview Carneal.

Witnesses and survivors of the Dec. 1 shooting said Carneal carried a pistol, shotguns and rifles into Heath High in the nearby community of West Paducah, then opened fire in the school's lobby just as classmates ended an informal prayer meeting.

Three girls were killed, and five other students were wounded.

Carneal is charged as an adult with murder, attempted murder and burglary. Court records show he admitted stealing the guns from a neighbor's garage days before the shooting.

The announcement that Carneal will use a mental health defense drew quick criticism from the families of the three dead girls, who said Carneal has not shown any remorse.

``An insanity plea is like ducking behind legal issues,'' said Gwen Hadley, mother of Nicole. ``It's not taking responsibility.''

Carneal faces life in prison without the chance for parole for 25 years on each of the murder charges. Kentucky law requires defendants to be at least 16 to be eligible for the death penalty.