Police raided the headquarters of a religious sect in central Japan on Monday and arrested 20 women for allegedly beating a member to death, an official said.

Motoko Okuno, 63, died last month at the Kigenkai sect's headquarters in the city of Komoro, allegedly after a mass beating, according to local news reports.

Police arrested the women late Monday on suspicion of injury leading to Okuno's death, according to a Komoro city police official. The official refused to give his name, citing policy.

Kigenkai, founded in 1970, is based on Japan's indigenous Shinto religion. Members sell purified water that they say can cure diseases for about $500 a bottle. It has about 400 members across Japan, according to news reports.

Among those arrested were a girl as young as 15 and a woman as old as 80, according to the Kyodo News agency. Earlier Monday, television video showed police streaming into the sect's headquarters to seize documents and question members.

Some news reports suggested Okuno, who owned a sushi restaurant, was killed as punishment for failing to carry out religious rites.

Police launched an investigation after doctors who examined her bruised body raised the alarm, Kyodo said.

Residents living near the headquarters told public broadcaster NHK they often heard drums beating from the compound.

Religious sects in Japan, a largely nonreligious society, have often been linked to crimes and attacks.

Members of the doomsday cult Aum Shinrikyo released nerve gas in Tokyo's subway system in 1995, killing 12 people. More than a dozen former members face the death penalty in the attack, including cult's former guru, Shoko Asahara. The cult remains under surveillance by authorities.