A victim of a VX gas attack allegedly committed by members of Aum Shinrikyo said Wednesday that senior cult member Tomomitsu Niimi, one of the six members believed to have been responsible, should receive the maximum punishment unless he repents.

"I met (Niimi) several times before the attack and saw how hard he was trying to discipline himself," said Hiroyuki Nagaoka, who heads a group that helps former Aum members and their families break their ties with the cult. "If he still thinks (that he needs to discipline himself), he should display remorse, or else receive the severest sentence."

Testifying before the Tokyo District Court in Niimi's trial, Nagaoka outlined the Jan. 4, 1995, attack, in which he was surreptitiously sprayed with the nerve gas as he left his home in Tokyo's Minato Ward.