Prosecutors on Tuesday sought life imprisonment for a former member of the Aum Shinrikyo doomsday cult for playing a major role in the 1995 sarin gas attack on the Tokyo subway system that left 13 people dead and thousands injured.

During the attack, Katsuya Takahashi, 56, acted as the driver for one of the cult members who released the deadly sarin on a packed subway train.

He thus played an "important" role in helping the cult carry out the attack, the prosecutors claimed in the Tokyo District Court.