KABUL: An Afghan soldier shot and wounded three Australian and two Afghan troops in southern Afghanistan, the third such surprise attack against Australians in the past five months, officials said on Wednesday.

The shooting comes after a string of attacks by “rogue” soldiers and police, or by insurgents who have infiltrated security forces.

Such attacks are especially damaging as the Afghan National Army (ANA) tries to win public trust before Afghan forces take full responsibility for security nationwide.

Foreign combat troops are due to leave Afghanistan at the end of 2014.

The ANA soldier opened fire with a grenade launcher and an automatic weapon from a position overlooking a patrol base in Uruzgan province late on Tuesday, Australia's Defence Force commander David Hurley said.

The Australian soldiers sustained wounds that were not life-threatening but serious, while the two Afghan soldiers also shot at the base were in a satisfactory condition, Hurley and a spokesman for the Nato-led International Security Assistance Force (ISAF) in Afghanistan said.

The Afghan soldier fled the scene in an army vehicle, Hurley said. ISAF said a search for him was still underway.

Tuesday's shooting followed a similar attack less than two weeks ago in Kandahar, southern Afghanistan, when an Afghan soldier shot and killed three Australian soldiers and an Afghani interpreter.

In May, an Afghan soldier killed an Australian service member who had been mentoring the Afghan army, ISAF said, an attack which also took place in Uruzgan province.

The Afghan soldier was later killed when he refused arrest, ISAF said.

The latest shooting prompted the Australian Greens political party to renew their call for Australia to withdraw its forces from Afghanistan, where it has around 1,500 troops.

But Prime Minister Julia Gillard, who made a surprise visit to Kabul in the past week, said Australia would stick with its military commitments in Afghanistan.

“As distressing as these incidents are, as dreadful as these incidents are, our mission in Afghanistan does need to continue,” Gillard told reporters in Melbourne.

“Training is pivotal to that mission and our purpose in Afghanistan is to deny Afghanistan as a country in which terrorists can train to wreak violence around the world.”

In September, an Afghan guard employed by the US embassy opened fire inside a CIA office in Kabul, killing an American contractor.