Taliban gunmen detained a senior official in Pakistan on Sunday, demonstrating their grip on a critical northwestern valley while pursuing a peace deal the United States fears will amount to a militant victory.

Police said armed men waylaid Khushal Khan and six bodyguards as they drove to Swat, where militants have defied an army offensive, beheaded opponents and burned girls' schools.

Hours later, Taliban spokesman Muslim Khan said the official had continued his journey after "having tea with our comrades," but officials could not immediately confirm his release.

The incident was the second to buffet a week-old cease-fire that has halted more than a year of fighting that has killed hundreds and driven thousands more from their homes. A Pakistani TV reporter was shot to death in the valley last week.

NATO and the U.S. have expressed concern that a peace deal could create a militant sanctuary in Swat, a former tourist haven less than 100 miles (160 kilometers) from the Pakistani capital, Islamabad.

Pakistani leaders insist they remain dedicated to defeating the Taliban and al-Qaida and that peace in Swat could ease the violence threatening their nuclear-armed nation's stability.

Khan was driving to Swat to take up his new post as its top administrator, part of government efforts to reassert its authority, at least in the main city of Mingora.

Swat police chief Dilawar Bangash accused "elements" within the Taliban of trying to sabotage the peace process.

However, the Taliban spokesman claimed that the militants had unspecified "issues" with only one of the men accompanying the official and that he was treated as a guest.

Syed Mohammad Jawed, the top government administrator for the surrounding Malakand region, said Khan was held due to a "misunderstanding."

"Hopefully he will be with us in a short while," he said.

Security forces and militants are observing a cease-fire in Swat while a hard-line cleric tries to persuade the Swat Taliban to renounce violence in return for the introduction of elements of Islamic law.

Officials say the legal concessions meet long-standing demands for speedy justice in Swat and fall far short of the harsh version of Islamic law favored by Taliban militants.

The peace plan does not involve the nearby tribal area along Pakistan's border with Afghanistan, where U.S. officials suspect al-Qaida leaders including Osama bin Laden have found refuge.