Kabul - Afghan and international forces killed 40 suspected Taliban militants in the latest clashes in southern and eastern Afghanistan, while a suicide bomber killed himself and wounded a civilian in the northern region, officials said Sunday. The police chief of Afghanistan's restive southern Zabul province claimed Sunday that Afghan forces backed by US-led coalition air support killed 22 suspected insurgents in a clash.

The militants ambushed a convoy of Afghan soldiers and international troops in the province's Shinkay district on Saturday night, sparking a fierce battle that lasted for four hours, Abdul Rahman Sarjang, the provincial police chief said.

Shortly after the battle erupted, Afghan police forces and coalition aircraft joined the fight and killed 22 insurgents, Sarjang said.

"The bodies of the militants are still on the battlefield and four of them have been identified to be Pakistani nationals," he said, adding there were no casualties on the joint forces side.

The US military in a statement also said US troops killed four insurgents in Shinkay on Saturday but it was not clear if both Sarjang and the military statement were referring to the same incident.

Taliban spokesman, Qari Mohammad Yousif Ahmadi said that only three of their fighters were killed in the gunbattle, but claimed that Taliban fighters killed 48 Afghan and international soldiers.

Due to the remoteness of the area, it was difficult to get independent verification of the conflicting accounts.

Meanwhile, NATO-led forces in the eastern province of Kunar killed 18 suspected militants in a clash in which close-air support and attack helicopters were also used on Saturday, the alliance said in a statement.

The NATO forces seized 10 AK-47s, rocket-propelled grenade launchers with ammunition, five radios and two hand grenades, the statement said, adding there were no casualties on the military side.

Separately, the first suicide attack since the fall of Taliban regime in late 2001 happened in the relatively peaceful province of Samangan province on Sunday, police chief Sharafuddin Sharaf said.

He said a bomber tried to enter the governor's office in Aibak, the provincial capital city, but his explosive-filled vest detonated prematurely in front of the government building, he said.

"The bomber who seems to be a boy of around 16 years was killed and a woman was wounded," he said, adding that the attack happened when the provincial governor was meeting with other local authorities.

In the south-eastern province of Khost, Afghan commando forces discovered and disabled a vehicle packed with explosives intended for use in a car bombing, the US military statement said.

The vehicle was left by the side of a road in Sabari district of the province, it said.

Police forces in the Garmsir district of the southern Helmand province identified and killed a would-be suicide bomber, who was approaching a police station on Saturday, the interior ministry said in statement.

The blast, which was triggered by the explosives-filled vest killed the bomber, but caused no other casualties, it said.

More than seven years since the fall of Taliban regime after the US military invasion, Taliban militants are still a force to be reckoned with.

The insurgents have gained more strength in the past three years, forcing the US government to plan the deployment of 21,000 additional combat troops and military trainers to contain the insurgency this year.

New forces will bring to 90,000 the number of international troops deployed to Afghanistan from 42 nations. (dpa)