ISLAMABAD, Pakistan (CNN) -- Taliban militants have suspended talks with the provincial government in the midst of fighting in the country's volatile northwestern region.
Pakistani soldiers on patrol in Buner district.
"Due to the military operation in Lower Dir ... we have decided to suspend dialogue with the (North West Frontier Province) government," Amir Izad, a spokesman for Tehreek Nifaz-e-Shariat Mohammadi (TNSM), a Taliban-aligned group, said Monday.
This comes after Pakistan's Frontier Corps launched an offensive against suspected militants and their hideouts in Lower Dir, which neighbors the violence-plagued Swat area.
The TNSM lost contact with Sufi Muhammed, an Islamist fundamentalist leader who has been negotiating on behalf of the Taliban, on Sunday, Izad said.
"We have not been able to get any information about his whereabouts, make contact with him, or his family," according to Izad. "We will not restart the dialogue until these operations stop."
The suspected militant hideouts targeted by the military are in Islampura and Lal Qila in Lower Dir. A "heavy exchange of fire" was reported at Kala Dag and Lal Qila, the Pakistani military said Sunday.
There were reports of many Taliban deaths, including that of an "important local commander." One security force member was killed and four others were wounded, the military said.
Army Col. Attiq Ahmed told CNN about the military operation, and a Taliban spokesman in the area confirmed it.
Taliban spokesman Mullah Mansoor Dadullah said the militants were "resisting the army operation."
The Taliban "know who the people are who raise their voices for the operation," Dadullah said. "We know them; they are on our hit list and we will target them."
Lower Dir is one of the districts included in a recent peace deal between the government and the Taliban.
The agreement signed by Pakistani President Asif Ali Zardari allows the Taliban to implement Islamic law, or sharia, in the region in exchange for an end to fighting. Under the Taliban's strict interpretation of sharia law, women would be prevented from even being seen in public without their husbands or fathers.
The peace deal encompasses the Malakand Division, which includes the following areas: Swat, Lower Dir, Upper Dir, Buner, Shangla, Chitral and Malakand. Kohistan, which is not in Malakand division, is also covered under the deal.
Last week, the Taliban overran large sections of the Buner district, bringing them within 60 miles of the capital, Islamabad, in violation of the peace accord. The takeover of Buner brought the Taliban closer to the capital than it had been since it mounted its insurgency.
A Pakistani government official said Friday that the insurgents had completely withdrawn from the district by the end of the week, but a human rights group said people in Buner were reporting that local Taliban remained in the district.
CNN's Nic Robertson contributed to this report.