LOW EARTH ORBIT — NASA directed five crew members to shelter inside a docked SpaceX Crew Dragon spacecraft on Friday. NASA Mission Control issued the shelter order at 9:04 a.m. Eastern Time while two Russian cosmonauts attempted to repair cracks in a transfer tunnel.

NASA spokesperson Bethany Stevens stated, "Out of an abundance of caution, NASA has directed all four of the agency’s SpaceX Crew-12 members and NASA astronaut Chris Williams to assume an elevated safety posture in the Dragon spacecraft while the repair is underway." The cracks, located in a transfer tunnel within the Russian service module, have caused an intermittent air leak for approximately six years.

Roscosmos, the Russian space agency, paused the repair procedure to collect additional measurements and data. A slow pressure drop in the transfer tunnel was detected by Roscosmos last month following the arrival of a Russian cargo spacecraft. Stevens said, "Following new leaks, Roscosmos has elected to proceed with a more extensive repair operation on Friday, June 5."

The air leak has been classified as a safety risk. NASA and Roscosmos have attempted multiple repairs on the cracks in previous years, and both agencies are currently investigating the underlying cause of the cracks. A NASA statement read, "We look forward to working with Roscosmos on a collaborative approach to address the leaks."

NASA later instructed the crew members to exit the spacecraft and resume planned operations. A NASA statement indicated, "We continue to work with our Russian counterparts, along with the rest of the international community that supports the space station, to arrive at a more permanent resolution."

Four members of the SpaceX Crew-12 mission, comprising two American astronauts, one European Space Agency astronaut, and one Russian cosmonaut, arrived in February. Three additional crew members, including one American astronaut and two Russian cosmonauts, arrived in November aboard a Russian spacecraft. The space station, which launched in 1998, is operated by five international space agencies, with daily operations coordinated by NASA and Roscosmos.