 Complete the following phrase:  The officially accepted cause of the explosion is considered to be violation of the rules of loading and transportation of explosives. Alternative theories by some, including Nizhny Novgorod Oblast governor Gennady Khodyrev, have believed the explosion was planned as a terrorist act or as the actions of foreign special services with the purpose of forcing instability in the Soviet Union. The Arzamas train disaster occurred exactly a year before the 