A man walks out of the office of the International Assistance Mission in Kabul on August 7.

Humanitarian aid groups have promised to continue their work in Afghanistan after militants murdered ten medical aid workers August 5th.

Officials say the seven men and three women worked for the Christian aid group International Assistance Mission. They were returning to Kabul after a trip to Nuristan province to provide medical care and supplies. Those killed were six Americans, one German, one Briton and two Afghans.

The Taliban claimed responsibility for the attack. It accused the aid workers of being spies and spreading Christianity.

Violence against aid workers has increased in recent years, even though international laws are supposed to protect them. Seventeen aid workers have been killed in the first half of this year in Afghanistan. Nineteen others have been kidnapped.

In Pakistan, seven aid workers from the Christian group World Vision were killed during an attack on their office in March. Officials believe militants were responsible for the attack.

The Humanitarian Policy Group has been studying violence against aid workers for more than ten years. The group released its latest report on the issue last year.

Abby Stoddard works with the international research group Humanitarian Outcomes. She helped write the policy group report. The report says that in 2008, 260 humanitarian aid workers were killed, kidnapped or seriously injured in violent attacks.

This was the highest number of incidents since the group began doing the research 12 years ago. Mrs. Stoddard says more than 60 percent of the incidents took place in three countries.

Abby Stoddard: "There has been a rather significant increase in major attacks against aid workers but this has been driven by the extreme violent environments centered in just about three countries, Afghanistan, Somalia and Sudan, particularly the Darfur region of Sudan."

Sri Lanka, Chad, Iraq and Pakistan also had many cases of violence against aid workers. Abby Stoddard says ongoing conflicts in the countries increase the risk of violence against aid workers.

Mrs. Stoddard called the recent murders in Afghanistan horrific. But she said they are not uncommon. She says incidents involving nationals instead of foreigners do not get the same level of attention.

And that's the VOA Special English Development Report, written by June Simms. You can comment on this report at our website, voaspecialenglish.com. And you can find us on Facebook, Twitter and YouTube at VOA Learning English. I'm Steve Ember.

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（來(lái)源：VOA 編輯：陳丹妮）