Tokyo police Tuesday arrested a member of Aum Shinrikyo on suspicion of stealing a transaction data management system from a major Japanese bank.

Tetsuro Isobe, 27, is suspected of stealing the system by copying confidential information about it from the bank's computers to the hard disk of his personal computer between November 2000 and April. Investigators from the Metropolitan Police Department found the hard disk in April at an Aum facility in Tokyo's Arakawa Ward, police said.

Isobe was contracted to work at a software development company in Tokyo's Minato Ward last November and worked at NTT Communications Corp., which subcontracted part of the development work for the bank system to the software company, police said.

NTT Communications, the long-distance and international call arm of Nippon Telegraph and Telephone Corp., was developing the system for the Mizuho Financial Group, which is headquartered in Tokyo's Chiyoda Ward.

The MPD arrested Isobe on suspicion of breach of trust and searched a house used by Aum in Tokyo's Setagaya Ward and four other places for evidence.

Last year, a group of Aum-related firms were found to have received contracts to develop computer systems for the central government and major companies, including the Defense Agency and the MPD.

Aum founder Shoko Asahara, whose real name is Chizuo Matsumoto, is on trial for a raft of heinous crimes, including the 1995 sarin gas attack on the Tokyo subway system in which 12 people were killed and thousands injured. Several other cultists have been convicted and sentenced.