Japanese police raided the headquarters of a religious cult Sunday following the death of a member under mysterious circumstances.
More than 100 investigators poured into the Pana Wave Laboratory's main center in Fukui state on suspicion that its members beat the victim, police said.
Recent media reports have identified the victim as Satoshi Chigusa, a 40-year-old assistant university professor, who died Thursday after being rushed to hospital from the cult's facility.
An autopsy linked his death to heat stroke and trauma from external injuries. Wounds that appeared to have been caused by a beating were found on his back, TV Asahi reported Sunday. No arrests have been made.
The Kyodo news service, citing police sources, said Sunday the group regularly beat its members with wooden sticks, believing it protected them from electromagnetic waves that it considers harmful.
The group has been under close scrutiny by authorities since May, when its all-white caravan of vehicles carrying members dressed head-to-toe in white robes blocked a mountain road in central Japan during a weeklong standoff with police.
The cult said it was seeking refuge from deadly electromagnetic waves generated by power lines and controlled by "left-wing elements." Members believe white fabric helps neutralize the waves that are harming their leader's health.
Their doomsday warnings and eccentric behavior have unnerved many Japanese, reminding them of the Aum Shinrikyo cult, which started out as a small yoga class and later carried out a nerve gas attack on Tokyo's subways in 1995 that killed 12 people and sickened thousands.
Pana Wave was founded in the late 1970s by Yuko Chino, 69, a self-proclaimed prophet who preaches a mixture of Christianity, Buddhism and New Age doctrines.