Aum Supreme Truth is still under the strong influence of its founder Chizuo Matsumoto--also known as Shoko Asahara--although its new leader, Fumihiro Joyu, attempted to reform the cult when he declared it had broken from the founder in February 2003.
Joyu's reform attempt drew opposition from some followers and he has not appeared publicly since. He announced he was undergoing lengthy religious training.
Since Joyu has gone underground, Naruhito Noda and four other senior leaders have been running the cult under the original organizational set- up, with Matsumoto as its leader in absentia.
Noda, 37, was arrested on suspicion of violating the Pharmaceutical Affairs Law on Monday. He allegedly was involved in the unlicensed sale of medicines.
In March, one month after the Tokyo District Court sentenced Matsumoto to death, one of the five senior members told dozens of Aum followers gathered at its Kanto region facilities, "Our guru will continue to be in the center of us."
The senior member also said: "Even if our guru is executed, he'll only perish in body. His existence will still be absolute."
Aum currently has about 650 live-in followers and about 1,000 lay followers. It has 26 facilities in Tokyo and 16 other prefectures.