WASHINGTON: The Secret Service is facing more embarrassing disclosures about lapses in presidential security after reports that an armed security contractor with a criminal record rode in an elevator with President Barack Obama.

On Sept. 16, the security contractor with three convictions for assault and battery rode on an elevator with Obama and his security detail at the Centers for Disease Control and Prevention in Atlanta, violating Secret Service protocol. The Washington Examiner and The Washington Post reported the details of that breach just hours after Secret Service Director Julia Pierson left a long hearing Tuesday at the House of Representatives.

During more than three hours of questioning by lawmakers, Pierson neglected to mention the breach that occurred just days before a knife-carrying army veteran climbed over the White House fence and sprinted into the executive mansion.

A Secret Service spokesman confirmed the Atlanta elevator incident late Tuesday but did not elaborate, citing an ongoing investigation of the episode. It was not clear whether the president or Pierson herself knew about the incident until recently.

Pierson got a vote of low confidence from the lawmakers, who called for additional reviews into the agency’s poor response. The chairman of the House committee with oversight responsibilities for the Secret Service called for an independent commission to do a “top-to-bottom” review of the agency.

“I am deeply concerned with the lack of transparency from the Secret Service regarding the recent security breach at the White House,” Republican Rep. Michael McCaul, the chairman of the House Homeland Security Committee, said of the Sept. 19 incident. “This latest episode adds to the growing list of failures from an agency plagued by operational challenges, cultural problems and reporting difficulties.”

At Tuesday’s hearing, Pierson said she is the one who briefs Obama on threats to his personal security and said she had briefed him only once this year, “for the Sept. 19 incident.” She also disclosed that shortly before the alleged intruder, Omar J. Gonzalez, scaled 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.

On Aug. 25, Gonzalez was stopped while carrying a small hatchet near the fence south of the White House, Pierson said.

Lawmakers were aghast, too, about a four-day delay in 2011 before the Secret Service realized a man had fired a high-powered rifle at the White House, as reported by the Post on Sunday. Pierson told the hearing the security plan for protecting the White House was not “properly executed” on Sept. 19 when the intruder sprinted across the White House North Lawn and through the unlocked front door of the mansion, knocking over a Secret Service officer and then running past the staircase that leads to the first family’s residential quarters. He ran far inside the White House’s first floor before being tackled by a Secret Service agent.