The bodies of the two Ethiopians were found on Tuesday by security teams from Birkot town, who had been alerted by a third WFP employee who escaped the attackers.
The WFP staff were travelling on Friday
from Kebre Dehar to Jigiga after a field mission, when they were stopped
men 55 km (34 miles) south of Degeh Bur, WFP said in a statement.
WFP executive director Catherine Bertini condemned the killings.
"The number of attacks on humanitarian workers worldwide has been on the rise, making it increasingly difficult to deliver relief assistance,'' she said in the statement.
Four other WFP staff have been killed in Africa this year.
Insecurity in Ogaden has increased in recent months because of tension on Ethiopia's border with Somalia, WFP said.
- Reuters - Thomson Reuters Foundation
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