Pakistani tribesmen are continuing their hunt for al-Qaeda fighters close to the Afghan border ahead of Tuesday's government-set deadline.
The authorities have threatened further military action if the tribesmen do not flush out the militants.
The fighters say they have not run into any resistance
About 2,000 tribesmen of the Zalikhel clan began their sweep on Sunday in South Waziristan.
More than 100 militants and troops were killed in a massive army operation in the region several weeks ago.
The tribal "lashkar" (army) has spread out in two groups through South Waziristan carrying rifles and rocket launchers.
Tribesmen said they had sealed off some mountain passes 20km (12.5 miles) from the region's main town, Wana, and demolished two houses of clansmen believed to have harboured militants.
So far they have not run into any resistance.
Troop build up
Local elder Malik Mir Zalim Khan told the Reuters news agency: "We are after them. These people are responsible
for the destruction of our houses. Our people have been forced to flee their homes because of the fighting."
The tribesmen have reportedly asked for a 10-day extension to the deadline.
The governor of North West Frontier Province, Syed Iftikhar Hussain Shah, warned on Monday that the time given to carry out the search was not indefinite.
He said future military operations depended on the outcome of the lashkar's actions.
"We don't want bloodshed. If there can be a peaceful solution of this problem we will prefer that," he said.
Pakistan wants the tribes to rid the Afghan border region of all foreign militants.
However, the BBC's Rahimullah Yusufzai in Peshawar questions whether using undisciplined tribal fighters will bring any results.
He says any new army operation will also be harder because the militants are now even more dispersed than before.
Pakistan's military has recently added to the tens of thousands of troops in the region and may be preparing another drive against the militants and tribesmen suspected of harbouring them.
Many al-Qaeda and Taleban fighters fled into Pakistan when the American-led military campaign began in Afghanistan at the end of 2001.
Al-Qaeda chief Osama Bin Laden and his Egyptian deputy, Ayman al-Zawahri, are thought to be in the area.
Pakistan is under heavy pressure to kill or capture them as the Americans and their Nato and Afghan allies step up operations on the other side of the border.