Russian Emergencies Minister Sergei Shoigu believes it premature to talk about the causes of the Tu-22M3 bomber accident.
The minister said the causes of the accident had to be thoroughly investigated. "Investigation errors always prompt new accidents in the future," said Mr Shoigu.
Mr Shoigu said if a technological breakdown had caused the accident, the equipment had to be improved while if a human error was to blame, pilots had to be trained better.
"In any event investigation must not be rash," added Mr Shoigu.
After the Tu-22 3M long haul aircraft crashed in the Novgorod Region, Russia's north-east, the flights of this type of aircraft were suspended, the Russian Air Force told RIA Novosti.
Russian Air Force Chief Commander Vladimir Mikhailov took the decision to suspend flights before the causes of the crash are identified.
The Tu-22M3 crashed in the Novgorod region at about 23.40 Moscow time on Thursday killing four crewmen on board.
Russian President Vladimir Putin announced the registration of the first vaccine against coronavirus. Russia has thus become the first country in the world to register the vaccine against the novel coronavirus