Michael J. Sharp, a Mennonite worker with the United Nations who was killed in the Democratic Republic of Congo in 2017, was awarded the United Nations Dag Hammarskjöld Medal on June 1 in New York City in recognition of service to the U.N.

The medal was created by the U.N. Security Council in 1997 to honor military, police or civilian personnel who lost their lives while serving with a U.N. peacekeeping operation.

Also receiving the honor was his colleague Zaida Catalan, who was also killed while the two were leading a U.N. investigation into human rights abuses and sanctions violations.

While not officially members of a peacekeeping mission, Sharp and Catalan were determined by Secretary General António Guterres to be deserving of the honor due to their dedicated service in the DRC, working on behalf of the Security Council’s Sanctions Committee. Last year had the highest number of U.N. peacekeeper fatalities with 132.

“We are forever in their debt,” Guterres said during a wreath-laying ceremony at the U.N. headquarters, “and they are always in our hearts.”

Michael Sharp’s father, John Sharp, said his son didn’t consider his role in the DRC to be part of the U.N.’s armed and blue-helmeted peacekeeping forces.

“But he kept the commanders informed of his activities and those of his team in the regions he was working, including Kananga and Kasia Province,” Sharp said. “We received condolences from some who said they took his abduction and death personally. They made great efforts to find the bodies.

“He also spoke about the occasional atrocities of some ‘Blue Helmets,’ whom he investigated.”

The medal is named after Dag Hammarskjöld, a U.N. secretary general who died in a plane crash in 1961 in what is now Zambia.