A German development aid worker injured in an attack on his vehicle in northern Afghanistan on Christmas Eve has died, according to local officials.

The aid worker, a consultant for Germany's state-owned KfW development bank who has not yet been identified, was taken to a hospital at a German army base where he died of his injuries.

An Afghan colleague was also injured in the attack. Both men were on the way to Mazar-i-Sharif and were involved in a project to build a road between the cities of Kunduz and Kholm.

A local police chief confirmed details of the attack, adding that the man had been warned several times not to travel without security protection.

"We had advised him several times not go alone and without bodyguards to the district but he did not pay attention," Abdul Rauof Taj, deputy police chief of Balkh province, told the news agency AFP.

The Taliban has claimed responsibility for the attack on their website.

'Deeply saddened': Merkel

German politicians denounced the attack on Saturday, calling it cowardly and barbaric and sending their condolences to the family of the victim.

"I am deeply saddened by the death of our aid worker and condemn this attack in the strongest terms," said German Chancellor Angela Merkel.

A government spokesman said there are hundreds of German development workers in Afghanistan, who Merkel said were crucial to the reconstruction of the country.

"This attack shows once again how unscrupulous the terrorists are," said Merkel. "They aren't interested in a better future for the country, but instead want to restore an inhuman dictatorship."

Merkel last week visited Mazar-i-Sharif, the main city in northern Afghanistan, where she met with Afghan President Hamid Karzai and General David Petraeus, the US commander of the international forces fighting the Taliban insurgents.

Echoing Merkel's comments, German Development Minister Dirk Niebel called the attack "cowardly," saying it was "aimed at the interests of the local population that once again shows the dangers that face civilian reconstruction in Afghanistan."

Aid workers are increasingly coming under attack in Afghanistan. According to the United Nations Department of Safety and Security, the number of attacks on UN workers went up 133 percent in 2010 compared to last year.

Germany has 4,800 troops in Afghanistan, most of whom are serving in the north of the country and some in a base at Mazar-i-Sharif. Berlin is to start reducing troop numbers in Afghanistan by the end of 2011, and plans to pull out of the country completely by 2014.

Authors: Holly Fox, David Levitz, Martin Kuebler (AFP, AP, dpa)

Editor: Sarah Harman