Police investigating the cult suspected in the Tokyo nerve gas attack focused their attention Wednesday on a woman arrested at an airport carrying a box filled with passports and lists of sect members.

The woman was arrested Monday at Naha Airport in Okinawa in southwestern Japan. She refused to answer questions and was being held for interfering with police duties, police said.News reports identified her as the 37-year-old wife of a senior member of the cult Aum Shinri Kyo, which is suspected in the subway attack that killed 11 people and injured 5,500 others. The sect denies involvement.

NHK television said the passports belonged to top cult members, most of whom have not been seen in public since the March 20 attack. Their whereabouts are unknown.

Japanese newspapers have reported that dozens of sect members applied for passports shortly before the attack.

Police raided the group's Naha office Wednesday and seized eight boxes of documents, officials said. Police would not describe what they seized in Naha, or provide more details about the contents of the box taken from the woman.

NHK also reported that the group, whose name means Supreme Truth, used a computer network last year to gather information about police stations around the country. The cult at the time was involved in several legal disputes.

Meanwhile, 220 police officers continued searching for evidence in Kamikuishiki, a cult commune near the foot of Mount Fuji.

In other raids on cult properties in the past 15 days, police have seized hundreds of barrels of chemicals they say can be used to make sarin, the nerve gas in the Tokyo subway attack.

They also have found large amounts of peptone, a nutrient that can be used to grow bacteria for biochemical research. Japanese news reports say police also found a bacteria that causes botulism, along with equipment that can be used to make chemical and biological weapons, at the cult compound.

Designs for a biochemical laboratory were in a large stack of documents seized from a cult member's car on March 23, the newspaper Asahi reported Wednesday.