The incident was tentatively blamed on heavy fog in the vicinity of the Khankala military base and not terrorist activity in the once-volatile North Caucasus republic.
Only crew members were on board of the Mi-8 helicopter at the time of the crash, the unnamed official said.
The surviving pilot was hospitalised.
This was the second helicopter-related incident in Russia in as many days. On Friday, another Mi-8 hit the ground with its rotor blade in Khabarovsk in the far east, crashing on launch.
No one was injured, but the crew faces up to seven years behind bars for violation of flight rules, investigators said.
Moscow: A military helicopter crashed in the Russian republic of Chechnya, killing three of four people on board, an official said.
First Published: Sunday, March 17, 2013, 08:44