In Hammarskjold’s Native Sweden, Hint of State Secrets Linked to His 1961 Death

In the decades since the death of United Nations Secretary General Dag Hammarskjold, his native Sweden has led the call for countries to disclose what they know about the air crash in central Africa that killed him — one of the most abiding mysteries in global diplomacy.

The Swedish authorities, however, have themselves refused a prominent researcher’s request for access to official Hammarskjold-related documents on grounds that they are classified under national security laws.

The decision, handed down by Sweden’s national archives on July 11 to a researcher, Hans Kristian Simensen, has raised questions about what the documents contain. It also seems to undermine Sweden’s stance that nations like the United States, Souith Africa and Britain should stop stonewalling requests for information.

“How can Sweden expect other countries to declassify relevant documents if Sweden is not doing the same?” the descendants of some of the 16 people killed in the crash asked in a letter to Sweden’s Foreign Ministry and a leading Swedish newspaper, Dagens Nyheter.

Mr. Hammarskjold and his peacemaking mission were just minutes from their destination — an airfield in what was then the British protectorate of Northern Rhodesia, now Zambia — when their chartered plane crashed early on Sept. 18, 1961.

Initial investigations by the colonial authorities blamed the crash on pilot error, but suspicion of foul play has never been far below the surface.

A prominent jurist retained by the current secretary general, António Guterres, has been looking into the case for two years and is believed to be nearing the final stages of his inquiry. The judge, Mohamed Chande Othman of Tanzania, is supposed to produce a report by the end of the current United Nations General Assembly session in mid-September, though it may be delayed.

His findings could write the final chapter in the long-running mystery, one replete with theories of conspiracy and skulduggery.