This collection of documents details the investigation into the September 16, 1999, apartment bombing in Volgodonsk (Criminal Case No. 173). Forensic analysis conducted by Military Unit 34435 in Moscow and experts T.V. Vinogradova and K.N. Stovbur confirmed the explosive charge was between 800 and 1850 kg in TNT equivalent, consisting of TNT, hexogen (RDX), aluminum, and likely ammonium nitrate. The reports highlight the difficulty in recovering firing mechanism remains due to the massive charge size, citing field experiments from the All-Russian Federal Nuclear Center in Sarov. Documentation includes requests from the Rostov UFSB for hospital records of victims and certificates regarding the destruction of a PAZ bus belonging to ZAO Energostroytservis. The investigative file mentions suspect A.I. Iskanderov and the use of sophisticated Western laboratory equipment for chemical analysis. Notably, the documents record that evidence boxes were sealed with obsolete stamps reading 'KGB of the USSR'.