Masato Yokoyama, 35, is the first cult member to receive the death penalty for the gassing that left 12 dead and thousands sick.

The BBC's Juliet Hindell: ''The judge said his intent had been to kill''

Two other cult members who participated in the March 1995 attack have already been sentenced to life imprisonment.

Three more disciples and the sect's leader are still on trial.

Yokoyama admitted carrying two packets of sarin on to a packed subway train.

But he said he did not realise the nerve gas was lethal, even though he held his breath while releasing it.

Yokoyama: Admitted carrying two packets of sarin

Yokoyama only managed to pierce one of the packets with an umbrella before making his escape, Tokyo District Court heard.

No one died on his train, but Judge Manabu Yamazaki said his intent had been to kill.

"It was a vicious and base act that ignored the dignity of human beings," he added. "He took a vital role in the act and his criminal responsibility is grave."

Shizue Takahashi, wife of a subway worker who died in the attack and now head of a victims' support group, said the death penalty for Yokoyama was "justified''.

Miori Noguchi, 29, who still suffers from bad eyesight and stress, added: "He deserved the death penalty. My hatred for Aum has not changed. Those who died cannot come back."

Inner circle

Yokoyama had studied applied physics at a top university before joining Aum, where he quickly became one of the guru Shoko Asahara's inner circle.

Cult leader Shoko Asahara was arrested in 1995

Shoko Asahara, who didn't personally take part in the attack, is on trial for allegedly masterminding the gassing. He also faces the death penalty.

In Japan, capital punishment is carried out by hanging, but executions usually take place many years after the court's decision.

On Wednesday, Aum promised to tone down its activities and stop recruiting members. It also said it would change its name.

The cult has never apologised for the subway gassing.