Six aid workers who were working on government projects to develop rural areas in Afghanistan were shot dead by Taliban militants on Monday, according to Afghan officials.
The six men were kidnapped by the Taliban on Sunday and were shot in the head when negotiations for their release failed.
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"We had gathered some elders to meet the Taliban to tell them that they (contractors)... worked for everyone in the country, but the Taliban killed them before they arrived for negotiations," said Herat Governor Fazlullah Wahidi.
Their bodies were found in the Gulran district of western Herat province.
In a separate incident, the bodies of six civilians were found in eastern Paktia province.
The Taliban have yet to comment on the killings, but such attacks have been on the rise since NATO announced it was preparing to withdraw combat troops next year.
Afghan President Hamid Karzai, who just a day earlier had called upon Pakistan to be involved in talks between his government and the Taliban, condemned the killings.
Speaking from Pakistan, Karzai said, "The killing of innocent engineers and workers shows that the Taliban and their foreign masters want Afghanistan to be an impoverished and underdeveloped country forever," apparently referring to Islamabad.
Earlier this month, another nine contractors who were working on building roads and a police officer were killed by insurgents in the same province.
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