ISLAMABAD (AP) - Pakistan warned militants Tuesday to leave a district just 60 miles (100 kilometers) from the capital or face military action, an indication that the government may be willing to expand an offensive in the Afghan border region covered by a much-criticized peace deal.

Interior Minister Rehman Malik’s stern comments came amid heightened U.S. pressure on the nuclear-armed Muslim nation to root out militants on its soil, though he and other Pakistani leaders have denied bowing to outside influence.

The peace deal with Taliban militants covers the Swat Valley. It imposes Islamic law in Swat, Buner, Dir and other districts that make up the Malakand division, a vast tract not far from Afghanistan. U.S. officials fear the deal creates a sanctuary for al-Qaida allies.

Supporters of the deal say it addresses long-standing local demands for a more efficient judicial system, a grievance exploited by the Taliban, and was the best hope for ending some two years of bloodshed in the Swat Valley.

Still, it appeared to have emboldened the Swat Taliban, who forayed south to Buner, a district just 60 miles (100 kilometers) from Islamabad. The militants began pulling out of Buner on Friday, but Malik said many had remained.

"Some 450 militants have been seen in Buner," he said. "I warn them to leave immediately. If they are spotted again and resist the government’s effort to establish its authority and maintain order then we will take action."

On Sunday, the military began an operation in Lower Dir, saying it was prompted by militant attacks on security forces and the abductions of prominent people for ransom. Malik said Tuesday at least 70 militants had been killed.

Mian Iftikhar Hussain, the information minister for Pakistan’s North West Frontier Province, downplayed the military action in Lower Dir, saying it was merely a short-term response to insurgent ambushes of security forces.

Analysts have said the offensive in Lower Dir is probably just a signal to the militants to stay confined to Swat and would likely be a limited operation.