The crash of a Russian airliner that killed all 65 of its passengers and six crew members is now being attributed to false flight speed data, BBC reported. The instrument malfunction occurred after pilots failed to turn on a heating system for the probes, leading to the freezing of a key speed monitoring device shortly after takeoff. The Russian media group RBK reported that the pilot had refused to follow the de-icing procedure, as they felt the temperatures were not cold enough to justify it. A criminal case has opened, highlighting negligent activity and a failure to follow aircraft operation rules as the causes of death for two or more people, reported the New York Post. A preliminary analysis showed the inability to correctly interpret the speed of the airplane led to the pilot’s decision to switch off auto-pilot to perform a series of manual maneuvers, one of which led to the crash of the jet just over five minutes after takeoff. Wreckage and was dispersed across an area of about 74 acres, just 50 miles southeast of Moscow. Aiding in the search for DNA samples and pieces of wreckage are more than 700 volunteers, along with Russia’s emergencies ministry, BBC reported. The crash of an Air France flight that killed 228 people on board in 2009 was attributed to the same iced-over speed probes as the Russian airliner, reported multiple news sources.