In two separate attacks, militants have reportedly shot dead 12 people, including six aid workers, in Herat Province.
The killing of workers connected with the Ministry of Rural Rehabilitation and Development and the World Bank's National Solidarity Program took place in Gulran district late on August 26.
Authorities say they were abducted by the Taliban on August 25.
Provincial Governor Fazlullah Wahidi said on August 27 that a delegation of elders had hoped to save the lives of the workers, but arrived too late to plead for a halt to the executions.
The aid workers had been trying to improve project management before foreign troops leave the country next year.
To the east, in Paktia Province, a local government spokesman said six civilians were found shot dead on a roadside on August 27.
It was not clear who was behind that attack.
Based on reporting by Reuters, AP, dpa, and RFE/RL's Radio Free Afghanistan