[##_1L|1230965326.jpg|width="120" height="101" alt=""|_##]A 41-year-old mental health patient has faced a northern New South Wales court charged with the decapitation murder of 82-year-old Armidale war veteran Mark Hutchinson. Mr Hutchinson's body was discovered in the backyard of his Markham Street home in Armidale about 2pm on January 13. Matthew James Woodroffe-Hill, a resident of Tamworth's Banksia Mental Health Unit, appeared in Tamworth Local Court today charged with the killing.

A slender man of medium height with short brown hair, Mr Woodroffe-Hill had his head bowed and remained expressionless throughout the hearing.

Described by homicide detectives as a resident of Tenterfield, police told the court he had been arrested at the Banksia unit about 10.30am (AEST) today after being questioned by detectives at Tamworth police station.

It is believed the arrest was carried out as a result of the work of Strike Force Penfold, a special task force set up within hours of the discovery of Mr Hutchinson's headless body.

Mr Woodroffe-Hill did not lodge a bail application.

Police applied to the court for forensic procedures to be carried out, asking permission to conduct a buccal swab and remove a hair sample to test his DNA.

Mr Woodroffe-Hill's Armidale lawyer David Clifton did not oppose the requests and permission was granted on condition they were completed at Tamworth police station by 9pm today.

The court was told Mr Woodroffe-Hill had not been a voluntary patient at Banksia.

It is understood that although he was not being held under section eight of the Mental Health Act, he had not been scheduled for release from the unit until May 31.

The matter was adjourned to Armidale Local Court for mention on May 23, but police said it may be up to six weeks before the results of the forensic tests were known.

Mr Clifton said outside the court that "this (the arrest) is tragic for him (Woodroffe-Hill), tragic for his family and for the wider family of the victim".

Mr Hutchinson was a former artillery gunner who served in Papua New Guinea and Borneo.

He had lived alone in his Markham Street home since 1985 and was known to his local community as a quiet but friendly man respected for his work with the local RSL and legacy war widows.

The crime initially baffled police, with robbery being ruled out early on as a possible motive.