At least 20 people, including an al-Qaeda operative, were killed Friday by a missile launched from a suspected US drone in a Pakistan tribal region bordering Afghanistan, security officials said.

'A US pilotless aircraft fired two guided missiles on the house of a person named Amanullah in the village of Asori in the Mir Ali sub- district of North Waziristan,' said an intelligence official who spoke on condition of anonymity.

The house was demolished and caught fire. People were trying to pull out the dead and the injured from the rubble but the fire was hampering their efforts, the official added.

'An al-Qaeda operative, Abu Akash, who was of Iraqi origin, and his four colleagues were among the 20 and 25 dead,' he said.

The first missile hit a four-wheel drive vehicle carrying Akash and his comrades just as it was entering the compound, which was targeted by another strike seconds later.

According to another intelligence official, who also declined to give his name, Akash was tasked by al-Qaeda leaders in Afghanistan with convincing the local Taliban to avoid conflict with Pakistani security forces.

'He was roaming the area talking to various Taliban leaders for the last two months and telling them that their strategy was harming the Islamist cause in Afghanistan,' he said.

Some of his lectures recorded on CDs were currently being distributed in the tribal region.

Pakistan's ungoverned tribal belt is believed to provide safe- havens for al-Qaeda and Taliban fighters launching cross-border attacks on US-led forces in Afghanistan.

But Islamabad has deployed more than 100,000 troops in the region and launched major offensives to restrict cross-border activity. Hundreds of people, including militants, security personnel and civilians, have died in the offensives.

The militants have also carried out dozens of suicide attacks across Pakistan, killing more than 4,000 people and forcing the government in Islamabad to take tough action against them.