On Sunday night, the Pentagon said that Austin was again hospitalized for medical examination due to bladder problems. Later, the department said that Austin transferred his powers to Deputy Secretary of Defense Kathleen Hicks.
"Tonight, after a series of tests and evaluations, the Secretary was admitted into the critical care unit at Walter Reed National Military Medical Center for supportive care and close monitoring," Dr. John Maddox and Dr. Gregory Chesnut said in a statement.
The statement added that it is now unclear how long Austin will remain in the hospital.
"The current bladder issue is not expected to change his anticipated full recovery. His cancer prognosis remains excellent," the statement read.