The gas attacks continue to haunt Japan

He was also convicted of burning the body of another cultist who died during training, which reportedly included being exposed to microwaves in a man-sized oven.

The Aum group hit the headlines in 1995 after releasing deadly Sarin nerve gas in the Tokyo subway, killing 12 people and injuring thousands of others.

Vicious killing

The court heard how Mr Ouchi had plotted with others, including the cult's guru Shoko Asahara, to throttle 21-year-old Mr Taguchi, to death with a rope after leaders learned he wanted to leave the group.

Aum leader Shoko Asahara is still on trial

Passing sentence, Judge Masazo Ogura said the murder was "vicious and inhuman".

The judge said although the order to murder Mr Taguchi had come from Mr Asahara, Ouchi had "agreed to the killing and acted of his own free will".

Toshiyasu Ouchi, 48, was also convicted of mutilating the corpse of cult member Naoki Ochi, 25, four years later by incinerating his body after he died during "training".

Manhunt

In 1998, Mr Ouchi became the subject of an international manhunt when he fled Russia after the authorities there began looking into his activities.

He was extradited to Japan following his arrest in Cyprus.

Aum guru Mr Asahara, 45, is still on trial for the Tokyo subway gas attack, which was carried out in revenge for a police crackdown on the cult.

Seven Aum disciples have already been sentenced to death for a number of crimes including the subway gassing, another Sarin attack in 1994 and the murder of an anti-Aum lawyer and his family in 1989.

The cult, which changed its name to Aleph this year - the first letter of the Hebrew alphabet. insists it is now a benign religious group.