Current military actions in the Rasht Valley are part of an annual anti-drug operation to stem the flow of opium and heroin smuggled out of Afghanistan, the world's largest producer, Tajikistan Drug Control Agency Director General Rustam Nazarov said.
But locals say the government is being very secretive about this operation, and using more force than in the past.
For experts the operation began after the Pakistan launched its offensive against the Taliban in the Swat Valley and after US President Barack Obama sent thousands more US troops to Afghanistan in a bid to defeat Islamic extremists.
Residents at the foot of the Pamir Mountains reported clashes with armed groups.
US military sources are convinced that al-Qai‘da is moving its forces out of Pakistan and Afghanistan and into neighbouring countries as a result of recent large-scale offensives.
Tajikistan is the smallest and poorest former Soviet state in Central Asia. In the wake of the collapse of the Soviet Union it went through a civil war as militant groups like the Islamist Movement of Uzbekistan (IMU) flourished.
After the war ended with a peace deal in 1997 extremist groups were pushed into Afghanistan.
The Tajik-Afghan border region is mountainous and scarcely inhabited, thus hard to control and easy to penetrate.
It has always been a place of refuge for the leaders of armed Islamic rebel groups.