At least 11 people have died in fresh violence in Pakistan's north-west tribal region, officials say.
Tens of thousands of soldiers are deployed in the border area
Eight militants and one soldier are said to have died in a clash with security forces near Miranshah, the main town in North Waziristan.
Earlier, unidentified armed men shot dead two local policemen in the area.
The attacks come days after the end of an 11-day ceasefire called by pro-Taleban militants battling security forces in the restive region.
North Waziristan is located near the border with Afghanistan and has been the scene of recent fighting between Pakistani troops and Islamic militants.
Tens of thousands of Pakistani soldiers have been deployed in the rugged terrain to hunt down Taleban and al-Qaeda militants.
Suspected militants are said to have ambushed a convoy of Pakistani troops near a check post on the road linking Miranshah with Razak.
Officials say the soldiers retaliated, sparking off a gun battle.
The Associated Press reports that the military, backed by helicopter gunships, are searching the area.
The clash came hours after gunmen killed two policemen on patrol in Miranshah's main market.
Security forces are battling against local militants who call themselves local Taleban aided, the army says, by foreign fighters linked to al-Qaeda.
In March, a group of local Taleban seized control of government buildings in North Waziristan and later attacked the regional headquarters of the paramilitary troops in Miranshah.
Since then officials say nearly 200 people have been killed in clashes or armed attacks, including many civilians.
The army says it is winning, but local observers say the Pakistani Taleban have established control over parts of North and South Waziristan, sidelining and sometimes killing pro-government tribal elders.
The BBC's Barbara Plett in Islamabad says the government is now trying to restore the political power of tribal leaders by setting up a grand council with representatives from across the tribal belt.
Are you from or do you know the tribal areas of Waziristan? Why do you think support for al-Qaeda and the Taleban has gained a foothold in this region? Send us your comments and experiences.
The BBC may edit your comments and not all emails will be published. Your comments may be published on any BBC media worldwide.