The five suspected militants were among 32 Afghans rounded up in Quetta, where Pakistani security officials said senior Taliban leader Mullah Obaidullah Akhund was arrested last Monday.

"They are Afghans aged between 20 and 25 and they came from Waziristan," said senior Quetta police officer Qazi Abdul Wahid, referring to a volatile Pakistani region on the Afghan border where Taliban and al Qaeda operate.

Wahid did not say if the five were members of the Taliban but said they were seized with compromising Islamist documents. They were being interrogated, he said.

He said 27 other Afghans had been picked up in raids in the city on Saturday night and they were also being questioned.

The Afghan government and foreign officials in Kabul have long said the Taliban were organising their insurgency against the Afghan government from Quetta, capital of Baluchistan province, which borders Afghanistan.

The insurgents have threatened to unleash a spring offensive in Afghanistan in coming weeks after the bloodiest year since their ouster in 2001.

Pakistan has been coming under mounting pressure from the United States and other Western governments with troops in Afghanistan to take action against Taliban operating from sanctuaries on the Pakistani side of the border.

Akund's arrest came hours after a visit to Pakistan by US Vice President Dick Cheney in which he asked Pakistan to do more against the Taliban.

"GLOOM"

The Pakistani government has not confirmed the arrest of former Taliban defence minister.

Officials say the government is worried about a backlash from militants and Islamist political parties bitterly opposed to President Pervez Musharraf's alliance with the United States in its war on terrorism.

Taliban spokesman have denied Akhund was captured, but Pakistan's the News newspaper said on Sunday a top Taliban commander and some Taliban officials were reluctantly admitting reports of his arrest appeared to be true.