Reuters - The wife of Pakistani Taliban chief Baitullah Mehsud was killed on Wednesday in a missile strike by a suspected U.S. drone in the South Waziristan tribal region, a relative told Reuters.

It was uncertain whether Mehsud was present when the missiles struck a house belonging to his father-in-law in Makeen, an almost inaccessible village in the heart of Mehsud lands on the Afghan border.

The United States has placed a $5 million reward on the head of Mehsud, an ally of al Qaeda widely regarded in Pakistan as Public Enemy No. 1.

Shortly before 1 a.m. (1900 GMT Tuesday), two missiles struck the sprawling, high-walled compound of Ikramuddin Mehsud, a cleric whose daughter married Baitullah Mehsud last November.

A senior intelligence official in Peshawar strongly doubted whether Mehsud would have been foolish enough to frequent the house of someone he was known to be close to.

But at least two militants were killed in the attack, according to a security official in Waziristan.

The relative said Mehsud’s wife was also among the dead.

Ikramuddin’s daughter was Mehsud’s second wife. Mehsud has no children by his first wife. Under Islamic custom, a man can have four wives.

“I confirm that the woman who was killed in the strike was the wife of Baitullah Mehsud,” the relative, who did not want to be identified, told Reuters by telephone.

He said four children were among the wounded.

The use of airpower is a contentious issue in the conflict raging in the ethnic Pashtun tribal lands straddling Pakistan and Afghanistan, as the guerrillas melt into the population and civilian deaths can harden support for the Taliban.

In the southern Afghan province of Kandahar, an air strike by Western forces late on Tuesday killed three boys and a man from one family, villagers said.

Shifting targets

U.S. missile attacks on Mehsud territory in South Waziristan have become more frequent in the past month. Pakistan has also bombarded the militant stronghold with air raids and medium-range artillery.

Mehsud declared himself leader of the Pakistan Taliban, grouping around 13 factions in the northwest, in late 2007, and his fighters have been behind a wave of suicide attacks inside Pakistan and on Western forces across the border in Afghanistan.

He is accused of being behind the assassination of Benazir Bhutto in December 2007, a charge he has denied. Conspiracy theories abound over who killed the former prime minister.

U.S. strikes against Mehsud increased after the Pakistan government ordered a military offensive in June.

U.S. drone attacks had hitherto mostly targeted lands held by Taliban leaders from the Wazir tribe as their territory borders Afghanistan and they have been more involved in the Afghan insurgency.

The army has sealed roads around Mehsud’s mountain redoubt and villagers have fled the area, but as the days have dragged on, doubts have grown about whether the army intends to launch a full-blown assault.

South Waziristan’s serrated mountain ridges, dried out river beds and gullies and low chaparral provide perfect terrain for guerrilla warfare, and Mehsud has a force of battle-hardened fighters variously estimated at between 10,000 and more than 20,000.

Analysts believe the army won’t risk opening another front until it has finished a campaign against the Taliban in the Swat valley, far to the east and closer to the capital, Islamabad.