After a 1 1/2 month summer recess, the murder trial of Aum Shinrikyo founder Shoko Asahara resumed Thursday with a grueling cross-examination of a prosecution witness by Asahara's defense counsel.

The defendant is on trial for his alleged involvement in a wide array of crimes, including the June 1994 sarin attack in Matsumoto, Nagano Prefecture, and the March 1995 gassing of Tokyo subways.

Kanya Kobayashi, a scientist with the National Police Agency, recounted on the witness stand his experience of examining blood, water and mud samples in the areas affected by the Matsumoto sarin attack.

He was a member of the Nagano Prefectural Police's scientists' team when the gassing took place. The defense counsel spent almost a full day cross-examining the witness as Kobayashi detailed three techniques used to analyze the samples, including one using a gas-chromatograph mass-spectrometer device.

Kobayashi testified that results of the gas-chromatography test on a sample of pond water at the residence of Yoshiyuki Kono, as well as samples of water from another area and mud, revealed they contained sarin.