Pakistan army sent more troops to prepare for a fresh push against hundreds of al-Qaeda men on the Afghan border as tribesmen made last ditch efforts on Thursday to avoid more bloodshed.
More than 100 people were killed in fighting between Pakistani troops and al-Qaeda militants and their Pakistani tribal allies near the western town of Wana last month.
Residents said many fresh troops had been moving into the dusty town in recent days.
"Troops equipped with heavy weapons have been coming into Wana for the past three days," one resident said. "We have never seen such a big deployment of troops in our area."
President Pervez Musharraf has vowed to clear foreign militants from the lawless tribal areas on the Afghan border. He blamed militants with links to the tribal areas for attacks across Pakistan, including two attempts on his life in December.
The movement of troops came as tribal elders sought to persuade fellow tribesmen to give up any foreign militants they might be sheltering in the South Waziristan region.
A traditional tribal assembly has sent a delegation to try to meet five tribesmen accused of sheltering militants.
Tribal elder Malik Qadir Khan said the team would call on the men to either give themselves up, leave the area, or give assurances that they would not shelter militants.
"If they refuse to accept these conditions, then we will take action against them," Malik Qadir Khan told the assembly.
The Zali Kheil tribe, to which the five men belong, agreed on Wednesday to raise a militia of 1,500 men to hunt the militants down.
Pakistani authorities set a deadline of April 20 for the elders to hand over foreign fighters, thought to be Chechens, Arabs and Uzbeks, and the tribesmen sheltering them.
Nek Mohammad, one of the tribesmen accused of harbouring al-Qaeda militants, in recent remarks published in local media, rejected calls to surrender, raising fears of more fighting.