The Afghan Taliban has killed six government workers kidnapped by them several days ago in western province of Herat, said a provincial police source Tuesday.

"The dead bodies of six employees of the Ministry of Rural Rehabilitation and Development were found early Tuesday morning in an area in Gulran district where they were kidnapped Sunday. All of them were shot dead," head of provincial criminal investigation department Israeel Khan told Xinhua.

He said the victims were working in a ministry project funded by the National Solidarity Program in the district, just northwest of the provincial capital Herat city, 640 km west of national capital Kabul.

Blaming Taliban for the shooting, police officials said that the killed included four engineers and two staff members of the project.

The armed outfit which launched annual rebel offensive in April has said anyone working for government and the NATO-led troops are legitimate target.

A total of 1,319 civilians were killed and 2,533 injured in conflict-related violence in the first half of this year, according to a UN report released in Kabul in July.

The report attributed 74 percent of the civilian deaths to the attacks of Taliban insurgents and other armed groups.

Up to 312 civilians were killed and 131 wounded in targeted killings across the country in the first half of 2013, according to the report.

In another development, one Afghan border police was killed and one was injured when the militants launched an attack on a police checkpoint in Torkhondi city along the border with Turkmenistan in northern Herat overnight, official confirmed, adding an investigation was underway into the incident.