Somali national Ibrahim Hussein Duale, 44, was killed "while he was doing his job," World Food Program Executive Director Josette Sheeran said in a U.N. statement.
"We call on all parties to allow us to do our job -- providing food to feed the hungry at this critical time," Sheeran said. "We are an impartial international organization and we need a minimum of security to serve the Somali people."
Duale was shot by three masked gunmen Tuesday while he was monitoring school feeding in a WFP-supported school in Yubsan village. Witnesses said the gunmen approached Duale while he was seated, ordered him to stand up and then shot him.
He is the third WFP staff member killed since August 2008 in Somalia. Five WFP-contracted transport staff were killed in the war-torn country in 2008.