More damaging revelations have emerged about the Secret Service amidst an uproar over an armed intruder who made it inside the White House. Secret Service officials previously said Omar Gonzalez, a former Army sniper who was carrying a knife, was caught near the main entry. But it emerged this week he actually managed to run past a stairway to the first family’s living quarters and through the East Room before he was apprehended. The Washington Post now reports the agent who caught Gonzalez was off-duty, but happened to come across him after his breach. Secret Service agents had also observed Gonzalez around the White House in the hours before he jumped the fence. Appearing before a House panel, Secret Service Director Julia Pierson apologized for the incident.

Julia Pierson: “It is clear that our security plan was not properly executed. This is unacceptable, and I take full responsibility, and I will make sure that it does not happen again. … I am committed to the following: a complete and thorough investigation of the facts of this incident; a complete and thorough review of all policies, procedures, protocols in place that govern the the security of the White House complex and a response to this incident; and based on the results of that review, a coordinated, informed effort to make any and all adjustments to include training and personnel actions that are necessary to properly ensure the safety and security of the president and the first family and the White House.”

Pierson came under repeated criticism throughout the hearing, with several lawmakers calling for an independent investigation of the Secret Service’s competency to protect the president. The outcry grew on Tuesday with news that an armed security guard with a criminal record was allowed to ride in the same elevator as President Obama in Atlanta earlier this month, a breach of protocol.