NASA ordered four astronauts aboard the Crew-12 mission to shelter in their SpaceX Dragon capsule and don spacesuits after detecting an expanding air leak in the Russian segment of the International Space Station. The leak, located in the PrK transition tunnel connecting the Zvezda module to a docking port, was first identified in September 2019 but has persisted despite repeated repair attempts; Russian cosmonauts are working to fix it while the international crew remains ready for emergency evacuation.