The US has boosted its use of drone-fired missiles since 2008 to step up its war against al-Qaeda and Taliban [Reuters]

At least 23 people have been killed after a pair of US missile strikes hit an alleged fighter training facility and a vehicle in a tribal region in Pakistan, local intelligence officials have said. 

One drone strike killed 18 people on Wednesday when it hit a compound in the Shawal area, which lies along the border that separates the South and North Waziristan tribal regions. The other struck a vehicle carrying five men.

The compound is believed to have housed a training camp for "extremists", Pakistani officials said.

Both regions are home to various fighter groups, including several involved in attacks on Western forces across the border in Afghanistan.

The area hit on Wednesday was on the North Waziristan side, in territory under the control of Hafiz Gul Bahadur, a warlord involved in the Afghan fight.

North Waziristan is the usual target for US missiles because it is home to more groups fighting in Afghanistan and because the Pakistani military has resisted US appeals to launch an offensive there. But this week's strikes had mostly hit South Waziristan or along the border of the two regions.

Since 2008, the US has boosted its use of drone-fired missiles to take out al-Qaeda and Taliban targets in Pakistan.