Pakistan authorities have arrested 16 tribal chiefs in South Waziristan who they say were not cooperating in rounding up al-Qaeda and Taliban elements hiding in the region.
Pakistani forces have been active in the South Waziristan tribal area
Officials based in Wanna told the BBC that the arrests, on Wednesday, were intended to encourage the tribes to assist Pakistani forces operating in the area.
Lying on the border with Afghanistan, South Waziristan is part of Pakistan's western tribal areas, semi-autonomous states which are often described as 'no-man's land.'
But local official Rehmatullah Wazir denied the move could further fuel tensions in the region, which is said to boast strong ideological ties with the Taleban.
He said the arrests were a calculated decision and would soon bear fruit.
Tensions have been running high in the region since the end of February after the death of 11 people - allegedly at the hands of Pakistani soldiers - on the Afghan border.
In recent weeks the Pakistani army has conducted several operations against al-Qaeda and Taleban suspects, who are believed to be hiding in the area.