The Pakistani army says it has been ordered by the government to begin military operations against al-Qaida-linked Taliban leader Baitullah Mehsud, but authorities are not giving details of the operation.  

Clashes have been reported between security forces and militants in Baitullah Mehsud's base of South Waziristan for weeks, but the military repeatedly denied opening a new front in its campaign against Taliban militants.

On Tuesday, however, the army confirmed Sunday's comments by a provincial governor that the military is preparing an all-out assault against Mehsud, leader of the banned group Tehrik-e-Taliban Pakistan.

Mehsud has claimed responsibility for a spate of recent terrorist attacks in Pakistan, including the bombing of the luxury Pearl Continental Hotel in Peshawar and last week's suicide attack in Lahore that killed one of the country's most prominent and moderate religious scholars, Sarfraz Naeemi. He has also been blamed for the assassination of former Prime Minister Benazir Bhutto.

The top army spokesman, Major General Athar Abbas, says the operation is in what he called "a preliminary phase." He revealed little about how troops would operate in the lawless and rugged terrain of South Waziristan.

"The operational details of how to target the network, the person himself, how the operation would unfold, these are necessary details [which] only at an appropriate time can be shared with the media," he said.  "It would be premature to say anything regarding the operation or technical details."

Abbas refused to confirm or deny whether U.S. and NATO troops across the border in Afghanistan would help the Pakistani army against Mehsud.  

The army has targeted Mehsud several times in the past with little success, except for peace deals that have quickly broken down.  The United States government calls him a key facilitator for al-Qaida terrorists and has offered a $5 million reward for information leading to his capture.

There are concerns that new fighting in Waziristan will spark a flood of civilian refugees, similar to the displacement of more than 2.5 million people after the army started clearing northwestern Swat Valley and surrounding areas of militants.  There have already been reports of people fleeing South Waziristan.

Abdur Rahim Mehsud, who is a member of Baitullah Mehsud's tribe in Waziristan, says the displacement of the local population has begun.

Mehsud estimates about a half a million people are on the move and many others are trapped.  He says the area is under military assault and that homes have been destroyed.  And Mehsud says, so far, the government has not provided any assistance or set up any camps.
Information Minister Qamar Zaman Kaira denied such reports during Tuesday's military briefing.

"There is no big movement of the people as you are mentioning, half a million, no. We are ready to cater if any problems come like IDP's," he said.  "We don't expect such a big number."

Meanwhile, the army is reporting progress in Swat Valley.   It says electricity is being restored to the main town of Mingora and that surrounding areas, including Piochar and Shangla, are completely secured.  Information Minister Kaira was so optimistic, he predicted people could begin returning to their homes within days.