Police on Monday searched five offices and facilities of the main successor group to the Aum Shinrikyo cult that was responsible for the 1995 Tokyo subway nerve gas attack.

The raids came after the group, now known as Aleph, allegedly recruited and collected tens of thousands of yen in membership fees from a woman in February without having her fill out the legally required paperwork.

The Hokkaido Prefectural Police raided a four-story building in Shiroishi Ward, Sapporo. The building is thought to be Aleph's largest facility.

Of the five locations police said they searched, two were in Sapporo and one was in Fukuoka. It wasn't immediately known where the other two were.

Members of the Aum Shinrikyo cult killed 13 people and injured more than 6,000 in the sarin attack on March 20, 1995. It renamed itself Aleph in 2000.

The police believe Aleph has been luring young followers without disclosing that it is a religious group and without informing them of its links to Aum and its criminal history.

According to the police, there were about 1,500 Aleph followers across the country last year.

The number of followers is on the increase, and many of the younger people who join its ranks are apparently unaware of Aum's criminal background.

Aleph has organized a number of yoga classes as a means of encouraging potential followers to join, according to the police.