Mansoor Dadullah, the brother of slain Taliban military commander Mullah Dadullah, and five others were challenged by security forces as they crossed from Afghanistan into Pakistan's southwestern province of Baluchistan. They refused to stop and opened fire, said army spokesman Maj. Gen. Athar Abbas.
"Security personnel returned fire. As a result all of them sustained injuries and all of them were captured," Abbas said. "Dadullah was arrested alive but he is critically wounded."
Earlier, a senior military official, speaking on condition of anonymity because he was not authorized to speak to journalists, said Dadullah had died of his wounds while being flown to a hospital with the other injured men.
Two Pakistani intelligence officials, declined to be named for the same reason, gave a different account of Dadullah's capture, saying he was nabbed during a raid on a religious seminary in a neighboring district. It was not immediately possible to reconcile the differing accounts.
Dadullah's capture comes amid growing Western pressure on Pakistan to crack down on Islamic militants launching attacks inside Afghanistan but increasingly destabilizing Pakistan itself.
In Afghanistan, officials reacted cautiously. Spokesmen at Afghanistan's Interior and Defense ministries said they had no immediate comment. Lt. Col. David Accetta, the top U.S. military spokesman in Afghanistan, said he could not confirm the report.
Dadullah rose in the militia's ranks as an important commander in southern Afghanistan after his brother was killed during a military operation in Afghanistan's Helmand province in May. Mullah Dadullah was the highest-ranking Taliban commander killed since the U.S.-led invasion of Afghanistan in 2001.
But in late December, Taliban spokesman Zabiullah Mujahid announced that Mansoor Dadullah had been dismissed from the movement for "disobeying orders" and conducting activities "against the Taliban's rules and regulations."
On Monday, Mujahid said Dadullah was still part of the Taliban movement, but that he was no longer an operational commander in southern Afghanistan. Mujahid said he had no comment about Dadullah's reported capture and death.
Dadullah told the AP in a phone interview in January that he remained a Taliban commander and had asked the militia's supreme leader Mullah Omar to dispel "rumors" of his dismissal.
He also claimed that he had met with al-Qaida's No. 2 Ayman al-Zawahri a few months ago but had never met with Osama bin Laden. He said Taliban and al-Qaida fighters in Helmand were fighting alongside each other and sharing tactics.
Abbas, the army spokesman, said Dadullah was captured near Gaddal, a border village in Qila Saifullah district in Baluchistan.
Two Pakistani intelligence officials, however, gave the location as Gwal Ismailzai village, in neighboring Zhob district. They said five militants, not six, were captured and wounded, some critically.
One of the officials identified those captured with Dadullah on Monday as Haji Lala, Khudai Dad, Khaliq Dad and Abdur Razzak. He said the injured suspects were whisked away by an army helicopter from Zhob airport to an unknown destination.
Afghan and Western officials say that Pakistan's border regions are a staging point for cross-border attacks on U.S., NATO and Afghan forces inside eastern and southern Afghanistan. Dadullah is the latest in a series of high-ranking Taliban militants to have been killed or captured
either side of the border in the past year or so. Pakistan, a key U.S. ally in the war on terrorism, concedes Taliban militants are active on its soil but has denied Omar and other militia leaders use Pakistan as a base of operations.
The violence in the country has often targeted politicians.
In Monday's suicide attack, Khan, the candidate for parliament supported by the Awami National Party, was campaigning in North Waziristan when he was wounded and his supporters were killed, authorities said.
Intelligence officials initially said he was killed.
But Afrasiab Khattak, a senior party official in the area, said Khan was hurt and that at least seven other people, including a local ANP leader, were killed.
Khan "is injured, but in stable condition and we spoke to him on the phone," Khattak told The Associated Press.
An intelligence official in the main northwestern city of Peshawar said the initial report he received in the aftermath of the attack was that Khan was dead. But later, the official said, he learned that the candidate had survived. The official spoke on condition of anonymity because he was not authorized to speak to media.
Mountainous tribal regions bordering Afghanistan are known to harbor al-Qaida- and Taliban-linked militants. The Pakistani government's control of the region is weak and communications are poor.
The Awami National Party is a secular party of ethnic Pashtuns seen as a rival to hard-line Islamic groups.
In July 2007, another prominent militant, Abdullah Mehsud, died in Zhob, apparently after he was cornered by Pakistani security forces. Mehsud was a Taliban veteran of Guantanamo Bay who began fighting Pakistani security forces after his release from the U.S. prison for terror suspects in 2004.
In March 2007, two months before Mullah Dadullah was killed in Helmand, Mullah Obaidullah Akhund, one of the two top deputies of Taliban supreme leader Omar, was arrested in Quetta -- where Afghan officials claim Omar is hiding.
In December 2006, another top Omar lieutenant, Mullah Akhtar Mohammad Osmani, died in a NATO airstrike in Helmand, near the Pakistan border.
Adm. Mike Mullen, chairman of the U.S. Joint Chiefs of Staff, held talks over the weekend with President Pervez Musharraf and Pakistani military chiefs, and told reporters that the militant threat in the country's border regions was growing. But he ruled out violating Pakistan's sovereignty by sending U.S. forces to fight there.