KABUL - NATO-led forces and Afghan troops killed three suspected militants during a raid Saturday in central Afghanistan, where insurgent attacks have spiked this year, officials said. At least two other militants died in an airstrike in the south.

The joint force was targeting insurgent commanders in a village in Logar province. The three suspected militants were killed in a gunfight following a call for them to surrender, the statement said.

About 3,000 U.S. troops serving under NATO-led command have been deployed in Logar and Wardak provinces that border Kabul in an attempt to clear these major insurgent strongholds from the capital's gates.

President Barack Obama has also ordered 21,000 new American troops to join the fight in southern Afghanistan, which is the Center of the revived Taliban movement that has made a comeback after their initial defeat in late 2001 during the U.S.-led invasion.

There are some 70,000 international forces in Afghanistan, including a record 38,000 Americans.

The infusion of the new U.S. troops in Logar this year has sent violent incidents in the province up, according to an assessment from Afghanistan NGO Safety Office, a Kabul-based group funded by Western donors that advises relief groups on security.

In the first two weeks of April, Logar accounted for 80 per cent of insurgent attacks in central Afghanistan, ANSO said in its biweekly report.

"Ultimately, the arrival of further forces has proven to be a destabilizing influence and has had a negative impact on the local population, primarily a result of methods utilized," ANSO said on its report, covering the first two weeks of April.

In southern Kandahar province, meanwhile, an airstrike on an underground bunker killed at least two suspected militants Saturday, a statement from the U.S. forces in Afghanistan said.

The force attacked multiple compounds in Kandahar's Maywand district, "to locate and capture a militant closely associated with the anti-Afghan forces leadership in Pakistan," the statement said.

It was not clear whether the target of the raid was among those killed.

Afghan and Western officials insist that the insurgency in Afghanistan is run and supported by Taliban leaders who now live in Pakistan, a charge denied by Pakistani authorities.