Islamabad  - At least 24 Islamist militants and four tribal policemen were killed in overnight airstrikes in Pakistan's north-western region near Afghanistan, officials said on Friday.

Pakistani jet aircraft and helicopter gunships targeted suspected Taliban positions Thursday in Orakzai, a relatively peaceful district in the country's lawless tribal region littered with Taliban sanctuaries.

The raids flattened several militant hideouts in the Ferozkhel and Ghiljo areas, killing at least 24 insurgents, a security official said on condition of anonymity.

The death toll could not be verified independently, but The News daily on Friday cited a Taliban spokesman as confirming that the rebels suffered 18 casualties.

Elsewhere in the troubled region, four policemen were killed late Thursday when insurgents attacked a security checkpoint near Khar, the main town of Bajaur tribal district on the Afghan border, another security official said.

A major offensive in Bajaur last year left more than 1,500 militants dead.

The district was described as a hub of al-Qaeda and Taliban fighters, who plotted and launched deadly attacks on US and NATO troops in Afghanistan.

The United States has welcomed Pakistan's ongoing operations against the militants across the north-west, as it places the country at the centre of its strategy to turn the tide against the Afghan Taliban.

Pakistani forces have nearly concluded their two-month operation in the Swat valley and its neighbouring areas, and are now gearing up for an offensive against top Taliban commander Baitullah Mehsud and his network in South Waziristan district.

Mehsud, who carries a 5-million-US-dollar bounty on his head for being a key al-Qaeda facilitator, is blamed for a spate of terrorist attacks since 2007 which have killed more than 2,000 people, mostly civilians.