Nine Afghan employees of a Czech aid organization were killed when militants attacked their guesthouse in northern Afghanistan early on Tuesday, officials said.

Nine Afghan employees of a Czech aid organization were killed when militants attacked their guesthouse in northern Afghanistan early on Tuesday, officials said.

"Those killed in Zari district of Balkh province include seven aid workers -- six men and one woman -- and two guards," deputy provincial police chief Abdul Razaq Qaderi told AFP, blaming the Taliban for the attack.

The victims were employees of People in Need (PIN), a Czech organization which has been delivering humanitarian aid around Afghanistan since 2001.

"Unfortunately last night unknown armed men attacked our guesthouse in Zari and martyred nine of our employees," a PIN official told AFP, requesting anonymity.

No group has so far claimed responsibility for the killings but the attack comes as the Taliban intensify their annual spring offensive despite repeated overtures from the government about reopening peace negotiations.

International aid workers have increasingly come under attack in Afghanistan despite the Taliban espousing an official policy that rejects attacks on humanitarian workers.