At the same time, it has emerged that the father of murder suspect Kipland Kinkel, 15, tried to enrol his son in a National Guard programme for troubled youngsters the day before the shooting, but the request was refused.

On Tuesday, hundreds of students returned to classes at Thurston High School for the first time since Thursday, when two boys were killed and 22 students injured in a gun attack at the school. Kinkel's parents were shot dead on the same day.

Nickolauson, who was 17, was buried with military honours as he had signed up for the National Guard three days before he was slain.

Students are being allowed time to come to terms with their grief

Classes at Thurston High School finished early so Nickolauson's schoolmates could attend the funeral. Counsellors were on hand in every class to help the pupils to deal with their shock and bereavement.

Students were later taken by the busload to Nickolauson's funeral. More than 900 people packed the Eugene Christian Fellowship to remember him as a quiet boy who loved computers and board games, and dreamed of a job as a systems analyst in the military.

The other murdered student, 16-year-old Ben Walker, was buried on Monday.

Meanwhile, at a juvenile detention centre across town, Kipland Kinkel remained under a suicide watch, wearing paper clothing in an isolation cell with 24-hour surveillance cameras.

He is charged as an adult with four counts of aggravated murder, alleged to have fatally shot his parents at home before driving the family car to school and firing 51 rounds from a rifle.

The day before, Kinkel had been arrested and suspended from school for allegedly buying a gun from another boy and putting it in his locker.

'Obsession with guns and bombs'

He was booked and sent home with his parents, who friends say were becoming increasingly frustrated with their son's growing obsession with bombs and guns.

That afternoon, National Guard officials say, they got a call from a person believed to be Kinkel's father anxiously seeking to enrol his son in a Guard program for troubled youngsters.

The man did not identify himself but said his son was 15 and had just been suspended from Thurston High. The minimum age for the program is 16 and those currently facing charges are not eligible.

There were no immediate details about the funeral for William Kinkel, 59, and his wife, Faith, 57, both popular foreign-language teachers.