The Pentagon’s second-in-command did not know that Defense Secretary Lloyd Austin was being hospitalized when she began assuming some of his duties last week, raising more questions about the stunning lack of transparency in the four-star Army general’s status.

On Friday, the Pentagon revealed to the public that Austin had been hospitalized at Walter Reed National Military Medical Center since Monday due to complications following a minor elective medical procedure. The announcement came almost immediately after notifying Congress, and only hours after Austin’s chief of staff reportedly informed top military officials of his condition in an email.

Defense Deputy Secretary Kathleen Hicks was apparently among several leaders ― including President Joe Biden, the commander-in-chief ― who were not told about Austin’s medical situation until at least three days after the 70-year-old checked into the hospital’s intensive care unit.

According to The Associated Press, Hicks was vacationing in Puerto Rico when she was asked to assume some of Austin’s responsibilities. Defense officials do not necessarily consider temporary transfers of power to be unusual, even if the reason for them is unclear.

The department had a communications setup that allowed her to do her job from the island while Austin was hospitalized. Hicks assumed some of Austin’s duties on Tuesday, but it was not until Thursday that she was allegedly informed of his hospitalization.

CNN first reported Sunday on the lack of transparency for Hicks, which was later confirmed by NPR and USA Today. All three outlets cited unnamed defense officials. HuffPost could not independently verify these reports.

Hicks “immediately engaged staff on the drafting of a public statement and congressional outreach” when she learned of Austin’s hospitalization, a defense official told NPR.

Pentagon spokesman Maj. Gen. Pat Ryder said that Austin is still in the hospital as of Saturday night, but resumed his full duties Friday evening from his hospital bed, according to the AP.

“I want to thank the amazing doctors and nursing staff at Walter Reed for the exceptional care they have delivered to me and for the personal warmth they have shown my family,” Austin said in a statement on Saturday. “I am very glad to be on the mend and look forward to returning to the Pentagon soon.”

“I also understand the media concerns about transparency and I recognize I could have done a better job ensuring the public was appropriately informed. I commit to doing better,” he continued. “But this is important to say: this was my medical procedure, and I take full responsibility for my decisions about disclosure.”

The secrecy around Austin’s illness ― including its severity and how soon he could be released ― is considered an extremely unusual practice, particularly at a fragile time when the U.S. is facing multiple high-profile national security challenges.

Iranian-backed militias have repeatedly attacked bases where U.S. troops are stationed in Iraq and Syria, resulting in retaliatory strikes that often involve top-level decisions by Austin. The U.S. is also leading a new international maritime coalition to patrol the Red Sea in an effort to push back against commercial vessel attacks by Houthi rebels in Yemen.

The Biden administration ― particularly Austin ― has also spearheaded the effort to supply Ukraine with training and weapons in their fight against Russia. The secretary has also been in regular communication with Israeli officials in their bombardment of Gaza.

The Pentagon Press Association, which represents members of the media who cover the military, sent a scathing letter on Friday to the Pentagon’s public affairs heads that said the four-day delay in announcing Austin’s hospitalization “falls far below the normal disclosure standards.”

“The public has a right to know when U.S. Cabinet members are hospitalized, under anesthesia or when duties are delegated as the result of any medical procedure. That has been the practice even up to the president’s level,” the letter read. “As the nation’s top defense leader, Secretary Austin has no claim to privacy in this situation.”

“At a time when there are growing threats to U.S. military service members in the Middle East and the U.S. is playing key national security roles in the wars in Israel and Ukraine, it is particularly critical for the American public to be informed about the health status and decision-making ability of its top defense leader.”