A “distracted” Security Forces guard allowed a homeless man to simply walk into Joint Base Andrews where he wandered the grounds unsupervised for more than five hours last month, an internal watchdog investigation has found.

Several reports said the man was wearing a hat that featured “mouse ears.”

The Feb. 4 security mishap at the Maryland facility, which houses the fleet of Air Force One planes regularly used by the president, occurred when the airman failed to properly vet the man’s license and credentials, allowing the intruder to board a C-40 aircraft designated for VIPs and senior government officials, according to a report by the Air Force inspector general.

There were two trainees aboard the plane who never questioned the man and said nothing as he exited the aircraft a few minutes later, the military report said.

The unauthorized civilian who entered the base was identified by The Hill as 36-year-old Joseph Armstrong, a homeless man who was arrested soon after the breach. He was ultimately turned over to local police on an outstanding warrant, reports said.

“There were three layers of breakdowns,” Lt. Gen. Sami Said, the inspector general, told reporters at a Thursday briefing. “The first one — the one that really should have stopped this ball from rolling in the first place is obviously the gate [where] we had a Security Forces airman — they were distracted and did not follow a procedure.”

Aside from the man being able to access the base at the southern Virginia Gate, he entered the flight line through a broken gate, and security personnel never saw him walking toward or boarding an aircraft that was parked there, Stars and Stripes reported.

Investigators said the man was unarmed and had no ill intentions.

“When we questioned him several times as to why he was there, his response was, ‘I just wanted to see airplanes,’ " Said told reporters.

The military also doesn’t believe the man ever entered an area where the Air Force One fleet is secured.

“This individual got nowhere close to that area of the flight line,” Said announced. “And we’re 100% certain he could have never gotten close to that because the layers of security are orders of magnitude higher.”

Meanwhile, the airman who let the man on the base was not identified. He was said to be fully qualified and trained to guard all four access points to the base, but told officials that he was distracted that morning by a personal issue, according to Stars and Stripes. He has since been reprimanded, but authorities have not revealed the punishment he faced.

The internal review, which began about two weeks ago, is continuing to focus on broader security measures and other issues at the base.