At least two Afghan security forces and 15 Taliban militants were killed as the Afghan security forces repulsed a Taliban attack on Kunduz city, capital of northern Kunduz province, on Saturday.

At least 13 civilians were killed, mostly children, in an air strike by "international forces" in the northern Afghan city of Kunduz late last week, the United Nations said Monday.

At least 14 civilians including women and children were killed in an Afghan-US aerial operation in northern Kunduz province, officials said Friday.

At least nine Afghan army soldiers were killed after Taliban militants attacked their checkpoints in northern Kunduz province, officials say

The event underlined the risks of greater use of air power under a new US strategy announced last year to try to force the Taliban to the negotiating table.

Taliban fighters launched a three-pronged attack on parts of the central-eastern Afghan city of Ghazni overnight, driving a Humvee packed with explosives into the entrance of a district governor's compound during the assault.

Hundreds of Afghan families have fled fighting between the Taliban and government forces near the northern city of Kunduz as the insurgents captured a strategic district soon after launching their annual spring offensive.

Taliban militants captured a district just outside the northern Afghan city of Kunduz on Saturday, officials said, pointing to renewed pickup in fighting after the insurgents announced their annual spring offensive last week.

A Spanish employee of the Red Cross who was abducted in northern Afghanistan has been released, the international charity said on Sunday, nearly a month after he was snatched by gunmen.

A US military investigation confirmed that dozens of Afghan civilians were killed in a special forces operation near the northern city of Kunduz last year, but found troops had acted in self-defence.

The top American general in Afghanistan promised on Saturday an investigation into civilian casualties caused by an air strike in support of Afghan special forces and their US advisors near the northern city of Kunduz this week.

US airstrikes early Thursday killed at least 30 Afghan civilians, including women and children, in the volatile northern province of Kunduz, officials said, after a Taliban assault left two American soldiers dead.