The United States Air Force has opened an investigation into allegations that a mortuary employee at Dover Air Force Base offered to show the remains of the astronaut John Glenn to inspectors during a visit they made to the complex in March.

Inspectors declined the offer and never viewed the remains, according to the Defense Department. Nonetheless, such an offer made by an employee would be considered “completely inappropriate,” Col. Patrick S. Ryder, an Air Force spokesman, said in a telephone interview on Friday.

The Delaware mortuary, which is the largest in the nation, had been temporarily holding the remains of Mr. Glenn, a former senator, at the request of his family, Mr. Ryder said.

Mr. Glenn was buried at Arlington National Cemetery about a month after the inspection occurred.

“The Air Force takes extremely seriously its responsibility to fulfill the nation’s sacred commitment of ensuring dignity, honor and respect to the fallen and care, service and support to their families,” Mr. Ryder said in a statement. “At the conclusion of the investigation, the Air Force will determine what further corrective actions, if any, may be necessary and appropriate. If any allegations of misconduct are substantiated, those involved will be held accountable.”

The secretary of the Air Force directed the Air Force inspector general’s office to investigate last week, and officials publicly announced on Thursday that the investigation was occurring, after the allegations were reported by The Military Times.

The Military Times reported that the allegations had been made in an internal memo by a director at the Defense Department. Mr. Ryder, the Air Force spokesman, said he could not provide copies of documents cited by The Military Times.

Mr. Ryder also would not name the person at the center of the investigation, citing privacy concerns and the developing nature of the investigation. He added that it would be “inappropriate to discuss specifics” related to the case.

But in a telephone interview late Friday, Bill Zwicharowski, the mortuary’s branch chief, said he was notified on Monday that the inspector general was investigating. He said he had been “detailed into another job temporarily” that was not “mortuary-related.”

Mr. Zwicharowski said the mortuary had been holding Mr. Glenn’s body for several months ahead of a planned burial on April 6, Mr. Glenn’s wedding anniversary. So Mr. Zwicharowski said he merely offered to show subject-matter experts the techniques that had been used in the embalming process to preserve Mr. Glenn’s remains.

“We were proud of the fact,” he said, “that we preserved him so well that he could have been viewed.”

Mr. Zwicharowski said he would have made the same offer had his team performed such extensive “preparation and care” on anyone.

“If it was Private Smith, it would have been the same thing,” he said. “I was not showing John Glenn as a display.”

Mr. Zwicharowski was one of several named whistle-blowers at the center of a 2011 scandal at Dover Air Force Base. Disclosures by these whistle-blowers prompted a monthslong investigation into failures at the facility, which found that three senior officials had displayed “gross mismanagement.” Those officials were disciplined but not fired.

Weeks later, a separate agency that investigates whistle-blower complaints issued a report alleging that officials at the base had retaliated against the whistle-blowers after they raised concerns about the way the service members’ remains were being handled.

On Friday, Mr. Zwicharowski said he believed there was “retribution involved” in the current investigation.

“There was absolutely no wrongdoing. Mr. Glenn received impeccable care,” Mr. Zwicharowski said. “He was treated with the honor, dignity and respect he deserves.”

Mr. Glenn, who became the first American to orbit Earth before starting a 24-year career in the Senate, died at the age of 95 in December. He was also a Marine Corps test pilot and is widely considered an American hero.

Dale Butland, Mr. Glenn’s former press secretary, said he spoke with the Glenn family on Friday.

“They have heard from the secretary of the Air Force who has assured them that they are investigating the incident and taking full responsibility,” Mr. Butland said in a telephone interview.