An armed private security agent was allowed on an elevator with President Barack Obama earlier this month in Atlanta, during a visit to the Centers for Disease and Control, a Secret Service official said on Tuesday, according to the Washington Examiner.

The Washington Post reported that a background check also showed the man had three previous convictions for assault and battery, according to the Examiner. The Secret Service official said the probe of the incident was part of an ongoing investigation by the agency.

In the Atlanta incident a security contractor with the CDC was operating the elevator carrying Obama and his Secret Service detail, the Examiner reported.

The man began taking pictures and video of Obama on his phone, prompting the Secret Service to take him aside for questioning after they left the elevator, the agency official said, according to the Examiner.

It was not until his supervisor appeared and asked for his gun that the Secret Service realized he was armed, the official said, the Examiner reported. Under agency rules, people with access to the president need special clearance to carry guns.

The incident occurred before another case involving a security failure at the White House where an intruder made it past the front lawn and into House, the Examiner reported.

The elevator incident happened on Sept. 16, three days before a man with a knife jumped the White House fence in Washington and ran into the executive mansion, according to the Examiner.

The Secret Service director fell under sharp criticism after the intruder incident, the Examiner said.

Secret Service Director Julia Pierson told a congressional committee on Tuesday: "This is unacceptable and I take full responsibility," according to the Examiner.

Secret Service agents are supposed to know who will have access to the president beforehand and anyone with a gun needs special clearance and may not be allowed to carry it when the president is onsite, the Examiner reported.