The captain of a U.S. Navy aircraft carrier facing a growing outbreak of the coronavirus is asking for permission to isolate the bulk of his roughly 5,000 crew members on shore.

The extraordinary move would take the warship out of duty in an effort to save lives. The captain of the USS Theodore Roosevelt says the spread of the disease is ongoing and accelerating.

He says removing all but 10 percent of the crew is a “necessary risk” in order to stop the spread of the virus. The ship is docked in Guam.