Gunmen killed six people, including the head of a Japanese aid agency, on Wednesday in an attack on their vehicle in Jalalabad in eastern Afghanistan, officials said.
The ambush comes a week after a grenade attack on a United Nations vehicle in Kabul heightened fears for those doing humanitarian work amid one of the world's longest-running conflicts.
Tetsu Nakamura, head of Peace Japan Medical Services, had been involved in rebuilding Afghan irrigation and agriculture and had recently been granted honorary Afghan citizenship for decades of humanitarian work in the east of the country.