JAPANESE police are tightening the net around top members of the religious sect Aum Shinri Kyo -- widely blamed for the deadly nerve-gas attack in Tokyo in March -- amid worries that group members will respond with violence if founder Shoko Asahara is arrested.
Last night, police were seeking arrest warrants charging Mr. Asahara and other sect leaders with direct responsibility for the nerve-gas attack on March 20 that killed 12 people and injured thousands. Raids on the sect's facilities near Mt. Fuji, where the ailing Asahara is believed to be in hiding, were expected after the warrants are obtained.
At the same time, some critics are accusing the authorities of manipulating the media and the media of being overly reliant on police in their coverage.
The result, these critics note, is that Aum is almost universally considered responsible for the gas attack and other similar incidents since then, even though none of its members have been formally accused of the attack during almost two months of investigation, much less tried in a court of law.
Early yesterday, police arrested an Aum member named Yoshihiro Inoue, the head of the group's self-styled ''intelligence ministry.''
Police say Mr. Inoue organized the subway attack, and have leaked details of one of his notebooks, including notations describing the schedules and ridership of the three subway lines targeted in the gas attack.
Police have characterized the notebook as a breakthrough, since it is the first material evidence they have obtained linking Aum with the incident.
Under Japanese law, police must build a case on physical, rather than circumstantial, proof to obtain convictions for murder.
With the investigation now in what appears to be its final stage, Japanese television networks have been airing hours of coverage of the case, in which lengthy talk shows are punctuated by occasional reports of an actual event. As they have been doing for weeks, Japanese newspapers are printing countless stories, virtually all attributed to the police, about the activities of Aum members and the progress of the investigation.
According to these reports:
*Two Aum members, Masami Tsuchiya and Seiichi Endo, have admitted to police that they were involved in the production of sarin, the gas used in the Tokyo incident. Another unnamed Aum member, also in police custody, has said he carried a vinyl bag containing sarin onto a subway car on March 20.
According to the latest police theory, Aum chemists produced the sarin at its facility near Mt. Fuji, and about a dozen conspirators were involved in releasing the substance at five points on three subway lines packed with commuters.
*Dozens of children taken from the Kamikuishiki facility have told government child-welfare workers that they were taught that Adolf Hitler is still alive. ''Hitler is a great soldier, and the man who is believed dead is just a substitute,'' one of the children said, according to a report in Sunday's Asahi newspaper. Another girl reportedly said she did not expect to turn 6 next year because she had been taught a devastating war would take place this coming December.
Asahara has expressed admiration for Hitler in his writings and has warned repeatedly of an impending apocalypse.
The sect apparently tried to construct a free-standing government that could preserve world culture in the aftermath of an Armageddon. Aum members have used this rationale to justify the massive amounts of chemicals and other industrial goods that police have seized from the group's properties
*Two Aum members, including a senior Aum leader named Hideo Murai who was stabbed to death last month by a man claiming to be angry at the sect, had their fingerprints surgically removed by doctors belonging to the group.
Revelations such as these have galvanized Japan for about eight weeks, contributing to an atmosphere in which Aum is deemed capable of anything.
Because several myster-ious incidents involving noxious or lethal gases have followed the subway attack, commentators have suggested that Aum members have stockpiled chemical weapons that they could use in the days ahead. Meanwhile, a few dozen people were sickened by strange-smelling fumes at a subway station in Yokohama last night.
The weekly magazine Shincho, in its edition released yesterday, speculated that the group could use radio-controlled helicopters to spread such substances in retaliation for arrests of sect leaders.
The weekly cited an unnamed reporter saying police had discovered evidence that Aum had acquired two or three devices, but had not located the helicopters themselves.
Tetsu Yamazaki, a playwright and media critic, wonders ''why has the Japanese media, both on television and in print, not criticized the police methods?''
He notes that the vast majority of media outlets simply source accounts to the authorities, while there has been virtually no critical assessment of the police work in the case.
''In this mood,'' Mr. Yamazaki says, ''the general public tends to believe that Aum is responsible for all the incidents [involving gas over the past two months]. I feel a danger of the authorities becoming too authoritarian because of the lack of media criticism.''