Military sources say up to 34 Tajik troops were killed in two separate incidents in the east of the country, in an area where a military operation against Islamist insurgents is under way.
However, officials have given a much lower death toll in what was described as accidents.
Military sources said up to 28 troops were killed when a military helicopter crashed
in Rasht Valley early on October 6 in what the unnamed sources said was a possible missile strike by insurgents.
An official statement said four members of the National Guard were killed and said the crash was due to technical failure.
Meanwhile, another six soldiers were killed in a landmine explosion in the same area. Several others were injured in what some military sources described as an accidental explosion.
Tajik government forces launched a special operation to apprehend militants in the Rasht Valley after at least 26 soldiers were killed in an ambush on a military convoy in the region in September.
The remote Rasht Valley is known as a haven for former fighters of the Islamist opposition that fought against government forces during the 1992-1997 Tajik Civil War.