aMystery deepened over the fate of Pakistan Taliban leader Hakimullah Mehsud on Monday following fresh reports of his death as his militant faction promised he would appear alive in a video.

US missile attacks have repeatedly targeted Mehsud, the head of Pakistan's powerful Taliban group and involved in a December suicide attack on the CIA in Afghanistan -- the deadliest attack on the US spy agency in 26 years.

Speculation about his death surfaced after a January 14 US drone strike in the Shaktoi area of North Waziristan, near the Afghan border, but Mehsud purportedly released two audio statements denying his demise.

On January 17, a day after Mehsud's last statement, a US drone carried out another attack that officials said also targeted the militant leader.

Killing Mehsud would be a coup for the United States, which stepped up its drone war in Pakistan after the warlord claimed the December 30 bombing that killed five CIA officers and two contractors in southeastern Afghanistan.

Pakistani officials said they had no confirmation of differing reports about his possible demise -- published by The New York Times and briefly on Pakistan's state television Sunday.

"So far there is no confirmation of his death. There is no credible report from that area (that Mehsud was killed or wounded)," chief military spokesman Major General Athar Abbas told reporters.

"This (reports of death or injury) is not from our sources. This is from outside sources... All the agencies are out to get the information," he added.

Asked about US drone attacks on January 14 and 17, Abbas confirmed reports were being circulated that Mehsud was wounded in the second attack.

Speaking to AFP from an undisclosed location, Tehreek-e-Taliban Pakistan (TTP) spokesman Azam Tariq denied "baseless and negative propaganda".

"Soon we will release his video showing he is alive," the spokesman said.

Earlier, a senior Pakistani intelligence official told AFP there were "confusing" reports that Mehsud was wounded when a US missile hit his vehicle on January 14 in the Shaktoi area.

He was reportedly taken more than 100 kilometres (60 miles) to Orakzai, in the far north of Pakistan's lawless tribal belt, for medical help but the official told AFP that the doctor in question had denied he treated Mehsud.

"It could be Mehsud's own bluffing game. The report may have been circulated to divert US attention because he was being repeatedly chased and targeted by the US spy planes," he said.

Pakistan, which has been fighting off accusations from the United States about not doing enough to eradicate the Taliban and Al-Qaeda menace on its soil, has placed a 50-million-rupee (600,000-dollar) price on Mehsud's head.

Prominent tribal affairs expert Rahimullah Yusufzai said the fact that state television station PTV said Mehsud had been buried in Orakzai gave the reports more importance but emphasised the region was an intelligence black hole.

"Orakzai is a tribal area. There is no government, no army... They (the military) have no means to verify. Local people are scared of the Taliban. They don't speak. The army will only wait for some intercepts," he told AFP.

The New York Times said Pakistani and US officials were increasingly convinced Mehsud died from wounds suffered on January 14, but had no proof.

A US administration official in Washington said intelligence reports reached about 90 percent certainty that Mehsud had died.

The paper said he was believed to have been buried in Pakistan?s tribal belt, the vast semi-autonomous area that US officials call Al-Qaeda's headquarters and where Pakistan has mounted an offensive against the Taliban.

Mehsud assumed leadership of the TTP -- blamed for the deaths of thousands of people in attacks across Pakistan -- after his predecessor, Baitullah Mehsud, was killed in a US drone strike last August.