Secret Service chief says White House breach 'unacceptable'

WASHINGTON (AFP) - The head of the Secret Service took responsibility Tuesday for security lapses at the White House, saying a recent intrusion by a knife-wielding man was "unacceptable" and would not occur again.

"This is unacceptable. I take full responsibility and it will never happen again," Secret Service director Julia Pierson told US lawmakers angered by a series of security failures at the presidential mansion.

Pierson, who was sworn in to the elite agency's top job in March 2013 after decades as a Secret Service officer, said a thorough investigation had been launched into how a US Army veteran carrying a knife could jump the fence, run across the lawn, dash through the front doors of the White House and run into the ceremonial East Room before being apprehended.

Saying the Secret Service had its "share of challenges" in recent years, she referred to a string of headline-grabbing security scandals that has put the service under intense scrutiny.

"I intend over the coming months to redouble my efforts, not only in response to this incident, but in general to bring the Secret Service to a level of performance that lives up to the vital mission we perform, the important individuals we protect, and the American people we serve," she told the House Government Oversight Committee.

Pierson got an earful from committee chairman Darrell Issa, who blasted the Secret Service for its "history of misbehaviour and security failures." He said it was "amazing and unacceptable" that an intruder made it into the White House.

"Inexplicably, Omar Gonzalez breached at least 'five rings' of security on September 19th," Issa told Pierson. "The fact is, the system broke down on September 19 as it did when the Salahis crashed a state dinner in November 2009, or when Oscar Ortega-Hernandez successfully shot at the White House on November 2011."