Homeland Security Secretary Jeh Johnson has paid tribute to outgoing director of the US Secret Service Julia Pierson in a statement.
Today Julia Pierson, the director of the United States Secret Service, offered her resignation, and I accepted it.
I salute her 30 years of distinguished service to the Secret Service and the Nation.
An independent panel of experts will investigate a incident where an intruder managed to climb over a White House fence and enter the building last month, US Homeland Security Secretary Jeh Johnson said.
Mr Johnson also named Secret Service veteran Joseph Clancy as Acting Director of the agency following Ms Pierson resignation.
Julia Pierson has resigned as the director of the US Secret Service, the Department for Home Security has confirmed.
It comes after she faced a committee of US politicians to answer questions over a series of breaches in White House security.
The breaches included an intruder jumping the fence of the White House who was apprehended inside armed with a knife and an incident in 2011 where bullets were fired at the South side of the historic building.
Another incident has come to light for which President Obama's Secret Service protection team is facing criticism.
A private security agent who had a gun shared an elevator with Obama in Atlanta on September 16, three days before the White House intrusion, a Secret Service official said.
The man, who was operating an elevator carrying Obama and his Secret Service detail during the president's visit to the US Centers for Disease Control and Prevention, aroused suspicion when he began taking pictures and video of Obama on his phone, the official said.
During questioning, the man's supervisor asked for his gun, startling Secret Service agents.
Under agency rules, people with access to the president need special clearance to carry guns.
The Washington Post, which along with the Washington Examiner, first reported the incident, said the man had three convictions for assault and battery.
The US Secret Service is currently 550 employees below its "optimal level" due to budget cuts, director Julia Pierson has told a House of Representatives committee.
She told the committee of US politicians that she had drafted in other special agents from around the country this summer to allow others to take annual leave.
Six people have jumped the White House fence this year, Secret Service director Julia Pierson has told US politicians.
"The Secret Service has apprehended sixteen individuals who have jumped the fence in the last five years, including six this year alone," Pierson said.
"In addition to fence jumpers, over the last five years, hundreds of individuals have approached the White House perimeter verbalising threats to our protectees or acting in a suspicious manner."
US Secret Service director Julia Pierson has admitted her agency "has had its share of challenges in recent years".
Pierson told a committee of US politicians, "I intend to lead the Secret Service through these challenges and restore our agency's reputation to the level of excellence that the American public expects,"
US Secret Service director Julia Pierson has said she takes "full responsibility" for the White House security breach earlier this month.
"What happened is unacceptable and it will never happen again," she said in a prepared testimony to a House of Representatives committee.
Pierson said she had ordered extra security measures around the White House immediately after the breach.
"It is clear that our security plan was not executed properly," she said, promising a complete review of procedures.
US Secret Service director Julia Pierson has said the recent White House security breach by a man carrying a knife was unacceptable and promised "it will never happen again."
"It is clear that our security plan was not executed properly," Pierson said in prepared testimony to a committee investigating the breach.