Up to 13 people have been killed in a suspected US drone attack in Pakistan's North Waziristan region near the Afghan border, security officials say.

The attack on Saturday occurred in an area 35km west of the region's main town of Miranshah.

The death toll is 13, including some foreigners, but  information is very sketchy because it's a town which is very  remote," one security official said on condition of anonymity.

Pakistani officials use the word "foreigner" to refer to suspected al-Qaeda and Taliban fighters, but the precise identities of the dead was not confirmed.

A local official said the compound that was hit belonged to Tariq Khan, who was described as a "facilitator of the Taliban".

Amir Shah, a resident of Waziristan, said drones were still flying over the area several hours after the attack.

'Safe haven'

With violence intensifying in Afghanistan, the US has launched more drone attacks on the Pakistani side of the border to destroy what it describes as "safe havens" for anti-government fighters.

The Pakistani government has protested to Washington against the drone strikes, saying they violated its territorial sovereignty.

But the US has kept up with its aerial attacks, accusing Islamabad of not doing enough to crack down on fighters who cross the border to attack US and Nato troops in Afghanistan.

Hundreds of Taliban and al-Qaeda fighters sought refuge in Pakistan's northwest tribal region after the US-led invasion of Afghanistan toppled the Taliban regime in late 2001.