Handout photograph shows US envoy for Afghanistan and Pakistan Richard Holbrooke (L) is holding a meeting with Pakistani former premier Nawaz Sharif and other party leaders in Islamabad yesterday. Photo: AFP

President Barack Obama's special envoy to Pakistan praised the country's "very significant" progress in taking back key territory from the Taliban and promised more weapons for the fight against extremists close to the Afghan border.

Richard Holbrooke began an official visit Sunday, his first since the reported death of the militants' leader, Baitullah Mehsud, in a CIA missile strike Aug. 5.

Heavy rain forced him to postpone a trip to the northwestern Swat Valley, where hundreds of thousands of refugees have begun to return after the military declared in July that it had ended Taliban control of the area, a US Embassy official said on condition of anonymity citing policy.

On Sunday, residents in Swat reported finding 18 bullet-ridden bodies lying in the streets, some of them believed to be those of militants loyal to the local Taliban chief.

"Eighteen dead bodies of militants were found in Barikot, Shamozai, Kabal and Kanju," a local military spokesman told AFP.

"They had been apparently shot dead by residents who fear that the Taliban might return. These militants were not killed in any military operation... The heads of some of the bodies had been smashed with hammers."

Atif-ur-Rehman, administrative chief of Swat district, confirmed that 18 bodies had been found but he had no further details.

Holbrooke told reporters traveling with him Saturday that the Pakistani military's success in Swat was a sign of progress, along with the apparent death of Mehsud, which he described as a serious blow to the militants.

"I cannot tell whether the Taliban have been destroyed or dispersed as a result of this operation until I go myself," he said. "But one thing that is quite obvious is that security forces regained Swat and Buner from the Taliban, which itself is very significant."

Washington has reportedly been anxious for Pakistan to capitalize on the momentum by launching a ground offensive in the Taliban-controlled tribal areas west of Swat including Mehsud's stronghold of Waziristan. However, Holbrooke said the timing was up to the Pakistani military, which has been launching aerial assaults against militant bases near the border.