Two US missile strikes on Wednesday killed at least 12 militants in Pakistan's tribal region near the Afghan border, officials said.

The first strike took place at 8:00 pm (1500 GMT) in Mizar Madakhel village, some 50 kilometres (31 miles) west of Miranshah, the main town in North Waziristan, followed swiftly by a second attack.

Eight militants were killed when the drone fired four missiles, hitting a vehicle and a compound which were being used by the insurgents, a senior security official in the area said.

He added that the second strike, which killed another four, took place after a brief interval. It targeted two vehicles which militants were using to pull out bodies from the site of the first attack.

"Three missiles were fired in the second strike which killed four rebels," he said.

Another Pakistani intelligence official confirmed the strikes and casualties. He said it was not immediately clear whether any "high value target" was present in the area, said to be the stronghold of local militant commander Hafiz Gul Bahadur.

US drone attacks routinely target Taliban and Al-Qaeda commanders in Pakistan's semi-autonomous tribal belt, which Washington calls the global headquarters of Al-Qaeda.

A US drone strike in Miranshah in February killed Mohammed Haqqani, a brother of Al-Qaeda-linked warlord Sirajuddin Haqqani, whose network is fighting against US and local forces in neighbouring Afghanistan.

More recently, three missiles fired by US drone aircraft killed five militants in Miranshah on Monday.

The covert US drone war against Al-Qaeda and Taliban leaders has focused increasingly on North Waziristan, a bastion of multiple militant groups, since a December 30 suicide attack killed seven CIA employees in Afghanistan.

North Waziristan borders Khost province, where a Jordanian doctor turned Al-Qaeda double agent blew himself up in the deadliest attack on the US spy agency in 26 years.

Taliban and Al-Qaeda-linked militants are blamed for a wave of suicide and bomb attacks across Pakistan that have killed more than 3,000 people since 2007.

The most recent attack claimed by Pakistan's Taliban faction was a suicide car bombing in Lahore on Monday that killed 15 people and destroyed offices used to interrogate suspected insurgents.

The bloodshed by militants has declined recently after spiking in late 2009, a reduction linked by officials to the suspected death -- still not confirmed -- of Taliban leader Hakimullah Mehsud and military offensives that have disrupted militant networks.

Pakistan's military claims to have made big gains against Taliban and Al-Qaeda strongholds over the past year, following major offensives in the northwestern district of Swat and the tribal region of South Waziristan.

The latest missile strike came hours after Afghan President Hamid Karzai arrived in Islamabad for talks with Pakistani leaders. His government has called for the extradition of a senior Taliban commander captured in Pakistan.