Two Sri Lankan Red Cross volunteers who had been abducted in the capital, Colombo, have been shot dead, the aid group has said.
The workers were to help repair tsunami damage
The bodies of the two men were found in Ratnapura district, about 100km (60 miles) south-east of Colombo.
The aid workers had been abducted by gunmen claiming to be police.
The defence ministry said police were investigating the deaths, which came amid heavy fighting between government forces and Tamil Tiger rebels.
"The two were part of a group of six aid workers brought from Batticaloa (in the island's east) for a training programme related to tsunami relief work last week," Red Cross director general Neville Nanayakkara told the news agency AFP.
"Some people in civilian clothes said they were from the police and wanted to see the identity cards of the six workers," Mr Nanayakkara said. "They took away two of them, saying it was for further questioning."
According to reports, both of the men were members of the country's Tamil minority.
The deaths mark the worst attack against aid workers in Sri Lanka since the killings of 17 employees of a French organisation in August.