The Washington Post is reporting a Secret Service team violated protocol when an armed security contractor, who was later found to have three prior convictions for violent offenses, was allowed on an elevator with President Obama during a Sept. 16 visit to Atlanta.

The Post reports three people familiar with the incident confirmed the events that took place when Obama was visiting the Centers for Disease Control and Prevention to discuss the U.S. response to the Ebola crisis.

According the sources in Post article, the contractor was using his phone to record video of Obama and refused to comply when Secret Service agents asked him to stop. The contractor was questioned by agents and a database check revealed the contractor's previous convictions for assault and battery.

The contractor was reportedly fired on the spot by a supervisor for a private security firm and agreed to turn over his gun. The Post said agents were not aware the contractor was armed.

“You have a convicted felon within arm’s reach of the president and they never did a background check,” Rep. Jason Chaffetz, R-Utah, told the Post. “Words aren’t strong enough for the outrage I feel for the safety of the president and his family."

The Post report was another blow to the Secret Service which is facing criticism from Congress over the recent breach of the White House by an intruder.

On Tuesday, the director of the Secret Service admitted failures in her agency's critical mission of protecting the president but repeatedly sidestepped key questions about how a knife-carrying intruder penetrated ring after ring of security before finally being tackled deep inside the White House.

Despite the extraordinary lapses in the Sept. 19 incident, Julia Pierson asserted: "The president is safe today."

Democratic and Republican lawmakers alike expressed the view that the latest breaches of White House security had blemished the storied agency, and several pressed for an independent inquiry into what went wrong. They were not assuaged by Pierson's vow that "I'll make sure that it does not happen again" or by the agency's own investigation.

"I wish to God you protected the White House like you protected your reputation here today," Rep. Stephen Lynch, D-Mass., told Pierson at a public hearing that was followed by a classified, closed-door briefing. Chaffetz, who has led Congress' investigation, said afterward: "The more I learn, the more it scares me."

Calm but defensive in testimony before the House Oversight and Government Reform Committee, Pierson disclosed that shortly before the intruder jumped the fence at least two of her uniformed officers recognized him from an earlier troubling encounter but did not approach him or report his presence to superiors.

—The Associated Press contributed to this report