Military activity in the remote Rasht Valley has picked up after a daring prison breakout in August
At least 23 soldiers have been killed in Tajikistan after a convoy was attacked by suspected Muslim fighters, according to a spokesman for the Central Asian nation's army.
The attack occurred on Sunday about 250km east of the capital Dushanbe, in the mountainous and inaccessible Rasht Valley near the border with Afghanistan.
Faridun Makhmadaliyev, a defence ministry spokesman, said on Monday that the soldiers were to rejoin a security post in the Rasht district when they were ambushed in the valley. Many soldiers were seriously wounded in the attack and evacuated for treatment.
Makhmadaliyev said the attackers included citizens from Afghanistan and Pakistan, as well fighters from the volatile southern Russian region of Chechnya.
The ambush comes at a time of rising tension following a string of blasts. A suicide bombing against a police station in the northern city of Khujand earlier this month claimed two victims and wounded 25.
Days later, a bomb was detonated in a disco in the capital, Dushanbe, wounding seven.
Military activity in the Rasht Valley has picked up in recent weeks as authorities seek to capture 18 men still on the run after a daring prison breakout last month.
Only seven of the 25 fugitives, who included many Muslim fighters and government opponents, have been captured.
The attackers were led by Mullo Abdullo, a Muslim commander who came to prominence during the civil war that devastated this former Soviet republic in the 1990s, Makhmadaliyev said.
Abdullo fled to Afghanistan after the end of the civil war in 1997, but he is believed to have returned to his native country some time last year in an effort to overthrow the government led by Emomali Rakhmon.
Most Muslim fighters gave up armed resistance after reaching an uneasy peace settlement with the government. But many returned with a fierce anti-government position over concerns they were being squeezed out of official positions granted to them as part of the peace agreement.