In an unusual deal, a small Russian logistics firm has agreed to airlift a highly radioactive shipment of cobalt-60 to North Korea — a powerful gamma-emitting isotope with both medical and military applications — marking a deepening of Moscow-Pyongyang cooperation that experts say could test the boundaries of U.N. sanctions.

An NK Pro investigation into Russian government procurement documents revealed a firm called Isotope sought out vendors to deliver the “class 7 dangerous cargo” from Vladivostok to Pyongyang’s Sunan International Airport

The firm describes itself as a subsidiary of the Rosatom State Atomic Energy Corporation in