More than 300 troops remain surrounded in Pakistan's Balochistan province, four days after clashes in which at least 23 people died, officials say.
The paramilitary troops are encircled by about 5,000 armed tribesmen in the remote town of Dera Bugti, provincial governor Owais Ghani told the BBC.
There is no independent confirmation of official claims, as Dera Bugti has been cut off since last Thursday's violence.
Tribesmen in Balochistan are demanding greater political and economic rights.
They also blame army members for raping a local doctor.
The troops besieged at their base in Dera Bugti are from the Frontier Corps - the main paramilitary force policing the province's tribal areas, Mr Ghani told BBC Urdu Online.
Those under siege include the local administration chief, Samad Lasi, he added.
Mr Lasi also spoke to the BBC by satellite telephone, saying Dera Bugti was extremely tense and that most of the civilian population had left.
Balochistan has been tense for several months
Tension rose in the area over the weekend after authorities confirmed that a murder case had been registered against the Bugti tribal chief, Nawab Akbar Bugti.
Pakistani authorities say Mr Bugti was behind an attack on a paramilitary convoy last Thursday that led to the clashes between tribesmen and troops.
Mr Bugti denies his men attacked the convoy, saying the clashes were deliberately instigated by security forces as a pretext for launching a military operation in the area.
He is one of the leading tribal chiefs in Balochistan who are pressing for greater political autonomy and a greater share of the revenue from the province's gas reserves.
The Bugtis say that attacks by government forces on Dera Bugti last week left over 50 dead, mostly civilians. The government denies attacking civilians and says the figures are exaggerated.
The clashes are the most serious since eight people were killed in several days of fighting in and around strategically important gas fields in the area in January.
Those clashes were sparked by the rape of a doctor, which Bugti tribesmen blame on an officer in the security forces.
Since then the army has moved extra forces into the area.
In the past two months tribal fighters have staged small-scale but almost daily attacks, hitting the security forces and the province's rail, power and communications infrastructure.