Analysis of a crashed Russian military plane's flight recorders has shown there was no explosion on board, officials said.
Lt Gen Sergei Bainetov stopped short of ruling out a terror attack as an explanation for Sunday's crash in the Black Sea, which killed at 92 people on board a Tu-154 aircraft, saying that "we aren't rejecting that version (of events) yet".
Lt Gen Bainetov, who heads the military commission investigating the incident, said a terror attack may not necessarily involve an explosion and that several factors might have contributed to the crash.
He added that flights of the military's Tu-154s have been suspended pending the investigation, but said they will likely resume after the probe is over.