Defense Secretary Lloyd Austin was released from Walter Reed National Military Medical Center on Monday, the Pentagon said, ending a two-week hospitalization he had kept secret for days after developing serious complications from a surgery to treat prostate cancer.

Austin, 70, said in a statement that he was grateful for the care he received, and thanked the medical personnel who tended to him and all who sent well wishes.

"Now, as I continue to recuperate and perform my duties from home, I'm eager to fully recover and return as quickly as possible to the Pentagon," he added. It was not immediately clear how long that may be.

Austin's doctors, John Maddox and Gregory Chesnut, said in a statement that the defense chief continues to recover well and, following medical advice, "will recuperate and perform his duties remotely for a period of time." The statement noted that he has "full access to required secure communications capabilities" at his home, where he will undergo physical therapy and "regular follow up."

The situation has garnered significant interest, not only because of Austin's position of authority, but because of the intensely private way he handled it. He initially underwent surgery to treat prostate cancer on Dec. 22 without informing President Biden and other senior officials in his administration.

On Jan. 1, Austin was in "intense pain" when he was transported to Walter Reed by ambulance from his Northern Virginia home and placed in intensive care, the Pentagon said later. But the Defense Department failed to disclose the medical crisis for days. A handful of officials close to Austin learned about his hospitalization Jan. 2, but the information was withheld from the White House until Jan. 4, and from Congress and the American public until Jan. 5.

Pentagon officials have struggled to explain the lack of transparency, including with Biden. Maj. Gen. Patrick Ryder, a spokesman, said that notification to the White House was delayed in part because Kelly Magsamen, Austin's chief of staff, was out sick with the flu. But it is not clear why no else made the call instead when multiple other senior Pentagon officials were aware of the secretary's hospitalization.

"We fully recognize that there are going to be many questions, in terms of notification timelines," Ryder said last week.

Those kept in the dark included Deputy Defense Secretary Kathleen Hicks, who assumed some of Austin's duties on Dec. 22, when he had surgery to treat his cancer, and again Jan. 2, after he was taken back to Walter Reed with complications. But in both instances, she was unaware he was hospitalized, Pentagon officials have said.

Magsamen has directed a 30-day internal review of the matter. The Defense Department inspector general also has launched a review, and Ryder said Austin's team will "fully support" it.

House Republicans have said they, too, will conduct an inquiry, raising the possibility of public oversight hearings during an election year.

White House officials, meanwhile, have directed a review of how senior government officials delegate authority to others when needed.

The White House has said Biden retains confidence in Austin's work as defense secretary. But they also have acknowledged frustration with the secrecy.

John Kirby, a spokesman for the National Security Council, said last week that he "can't answer" why the hospitalization wasn't "shared widely" in the Defense Department.

"It's not good, it's certainly not good," Kirby told reporters. "Which is why, again, we want to learn from this. We want to make sure it doesn't happen again."