Was investigating Max Lazovsky gang that had carried out earlier bombings. From Blowing Up Russia: "On April 12 1997 at the age of 39 Tskhai died suddenly from cirrhosis of the liver, although he didn’t drink or smoke. Presumably he was poisoned by the FSB because he had discovered the identities of the true leaders of Lazovsky’s group and realized exactly who had organized the explosions in Moscow. "