Five Afghan policemen have been killed retrieving the bodies of Macedonian hostages believed to have been killed by the Taleban, officials say.
The officers died when a roadside bomb hit their convoy of vehicles, which was already carrying the dead hostages.
The bodies of the four Macedonians, who were seized last week in the south of the country, had been retrieved in a mountainous area of Kandahar province.
Taleban militants say they captured and shot dead the four men.
The Macedonians were employed by a German cleaning company contracted to US-led forces. Earlier reports described them as Albanians. Four Afghan guards seized with them were later released.
Regional governor Asadullah Khalid said the hostages' bodies were found in the Maiwand district, on the border with Helmand province.
"The police [convoy] bringing the dead bodies of these four foreigners was hit by a roadside bomb on the highway between Kandahar and Maiwand," Mr Khalid said.
"One of the vehicles was hit and the others in the convoy continued on to Kandahar with the bodies."
Sound of gunfire
Taleban spokesman Qari Mohammad Yousuf on Monday said at the weekend the four foreigners had been shot dead.
"We will kill anyone who is helping the Americans," he told the BBC.
One of the freed Afghans said they had been stopped by a group of 20 men dressed as police as they left Helmand for Kabul on Saturday morning.
"They tied our hands and feet and blindfolded us," the man, who did not wish to be named, told the BBC.
He said they heard the sound of gunfire after the Macedonian hostages were led away.
Ecolog, the company the men worked for, is a German firm that treats dirty water at US and Afghan army bases.
There have been several incidents in recent months involving the kidnapping of foreigners in Afghanistan.
Some have been killed, including a Briton found dead last September, an Indian killed in November and a Nepalese man who died last month. In other cases, foreigners have been freed, reportedly after ransom money was paid.