At least three Afghan army soldiers were killed and several wounded on Friday when Taliban gunmen attacked a military headquarters in northern Afghanistan, officials said.

The attack occurred near a mosque on the base in Mazar-i-Sharif, the capital of Balkh province, as soldiers were leaving Friday prayers, according to an army officer who asked not to be named as he was not authorised to speak publicly.

The Western-backed Afghan government is locked in a prolonged war with Taliban insurgents as well as other militant groups.

Taliban spokesman Zabihullah Mujahid said the fighters set off an explosion, allowing suicide bombers armed with small arms to breach the base.

"Our fighters have inflicted heavy casualties on the Afghan army stationed there," he said.

Another army officer reported that the attackers used military uniforms and vehicles to pass three checkpoints before launching their attack.

The base is the headquarters for the Afghan National Army's 209th Corps. It covers most of northern Afghanistan, including Kunduz province, which has been the scene of heavy fighting.