The announcement Sunday by Muslim Khan, a spokesman for the Pakistani Taliban, comes a day after the Taliban in Swat freed a Chinese engineer held captive for nearly six months. Khan says he was freed as a goodwill gesture.
It was not immediately clear if a ransom was paid or militants were freed in exchange for Long Xiaowei's freedom.
However, Khan claimed the militants freed the Chinese captive after the government agreed to impose Islamic law in their region.
Swat, a former tourist haven, is believed to be largely under militant control despite a lengthy army offensive.
"That was our only demand," Khan told The Associated Press via telephone. "Once Islamic law is imposed, there will be no problems in Swat. The Taliban will lay down their arms."
Pakistani government and military officials either could not immediately be reached or declined comment Sunday on what secured the Chinese engineer's freedom.
Pakistan's government has made promises in the past to enforce already approved regulations relating to Islamic law in parts of the northwest as an olive branch in peace talks with militants.
Paying ransom or releasing militants in exchange for a hostage is not unprecedented in the Pakistan-Afghanistan region, though officials are generally loathe to confirm the terms because of concerns it might spur more kidnappings.
Earlier this month, a Polish geologist held by Taliban fighters was apparently beheaded in a video obtained by news media and believed by the Polish government to be authentic. On Friday, the kidnappers of American U.N. official John Solecki threatened to kill him within 72 hours and issued a 20-second video of the blindfolded captive saying he was "sick and in trouble."
The abductions have underscored the overall deteriorating security conditions in Pakistan, a critical U.S. ally in the fight against terrorism, as it battles a Taliban insurgency in its northwestern regions bordering Afghanistan. On Saturday, a U.S. missile strike on a compound in an area where dozens of Taliban militants had gathered killed 27 people, intelligence officials said.
China also is a major ally and longtime financial supporter of Pakistan, and the Chinese Foreign Ministry said Beijing attached high importance to the case of the kidnapped engineer.
Long was freed Saturday and taken to the Chinese Embassy on Sunday morning, said Yao Jing, deputy head of China's mission in Islamabad. The engineer was in good condition and was expected to go back to China after a medical checkup, China's Foreign Ministry said.
Long and fellow telecommunications engineer Zhang Guo were kidnapped in August in the Dir region of northwestern Pakistan. They both escaped in mid-October, according to China's state-run Xinhua News Agency. Long hurt his ankle and was recaptured, while Zhang got away.
The Chinese ministry said Long arrived at the embassy under the escort of Pakistani military and police, but did not say how he came into Pakistani custody. Yao said he did not know if a deal with struck with the militants.
(Left: An image from mobile phone footage purportedly showing John Solecki, a seized American U.N. worker. The kidnappers delivered the video to a Pakistani news agency along with a threat to kill Solecki within 72 hours unless its demands were met.)
A U.N. statement said it was aware of a demand by the kidnappers for the release of 141 women allegedly held in Pakistan and was seeking "urgent contact to discuss ways of securing [Solecki's] release."
Meanwhile, Baluchistan provincial government spokesman Syed Kamran said it was offering a $31,363 reward "for any information leading to the recovery of the kidnapped U.N. official."
Pakistan Interior Ministry chief Rehman Malik has said the abductors' demand was "highly unrealistic."
"I have shared that list of 141 women with authorities and all intelligence agencies. It does not have any reality," he said.
Tensions are especially high following the apparent slaying of the Polish geologist, Piotr Stanczak. If confirmed, it would be the first killing of a Western hostage in Pakistan since American journalist Daniel Pearl was beheaded in 2002.
Poland has asked the U.S. for help tracking down the Taliban militants suspected to have had Stanczak, whose body has not been recovered. Warsaw also has plans to issue an international warrant for their arrest.
Many Pakistanis believe the country is fighting Islamist militants, who have enjoyed state support in the past, only at Washington's behest. Disdain for the U.S. has risen as it has stepped up the missile strikes.
The strike on Saturday appeared to be the deadliest yet by American drone aircraft that prowl the border area. Two intelligence officials said dozens of followers of Pakistan's top Taliban leader, Baitullah Mehsud, were in the compound that was hit. They spoke on condition of anonymity because they were not authorized to speak to the media.