A decorated Iraq war veteran who scaled a fence on Friday night and got into the White House had more than 800 rounds of ammunition in his car and had been arrested in July with a sniper rifle and a map on which the executive mansion was marked, a federal prosecutor said on Monday.

An internal review of the United States Secret Service will examine how Omar Gonzalez, 42, made it into the White House before being stopped, his previous interactions with the Secret Service, and what must be done to prevent future security breaches.

The Secret Service is charged with safeguarding the leaders of the United States and visiting heads of state and government, and with protecting the country's economy by watching over its financial infrastructure and payment systems.

White House Security

Omar J. Gonzalez is accused of scaling a fence and making it into the White House before the Secret Service stopped him. (Carolyn Kaster/Associated Press)

Secret Service Director Julia Pierson, who ordered the review, has been asked to testify about Friday's security breach before a House of Representatives' oversight committee hearing scheduled for Sept. 30.

The agency is considering ways to expand the security zone around the White House to keep the public farther away and to do more screening of people in the area.

The Secret Service has stepped up security around the grounds on Pennsylvania Avenue, with some guards openly holding weapons and others escorting dogs.

A member of security asked CBC's Lyndsay Duncombe to step off the White House sidewalk while she was recording a TV news clip about the security breach.

When Duncombe asked why, the woman told her news agencies are not allowed to film on the sidewalk, though CBC's cameraman was not on the sidewalk.

"I'm asking you to go off the sidewalk. If you choose not to, I will ask law enforcement to come in and deal with it," she said. Duncombe complied with the request.

Friday's incident is the latest in a string of lapses involving the Secret Service, including a prostitution scandal in 2012.

"These significant security breaches reveal our weaknesses as well as our response capabilities to our nation's enemies," Darrell Issa, the Republican chairman of the committee, said in a statement.

Obama and his family had left the White House for a weekend at Camp David when Gonzalez climbed the fence and ran across the north lawn of the complex in full view of tourists on Pennsylvania Avenue.

Asked on Monday whether he has confidence in the agency, President Barack Obama said, "Secret Service does a great job, and I'm grateful for the sacrifices they make on my behalf and my family's behalf."

Charge carries up to 10-year prison sentence

Gonzalez, who retired from the Army on disability in 2012, had been living in Texas.

In July, he was arrested by Virginia State Police for reckless driving, eluding police and possessing a sawed-off shotgun. Police inventoried 11 guns in the vehicle including shotguns, handguns, and sniper rifles, and a map of Washington, DC, police records showed. Gonzalez was released on bond after the arrest.

'These significant security breaches reveal our weaknesses as well as our response capabilities to our nation's enemies.' - Darrell Issa, House of Representatives' oversight committee chairman

On the map, which was tucked into a Bible, the White House and the Masonic Temple in Alexandria, Virginia, were circled, federal prosecutor David Mudd told a federal judge on Monday.

In August, he was stopped, but not arrested, while walking along the south fence of the White House with a hatchet in his waistband.

After being apprehended on Friday, Gonzalez told a Secret Service agent "he was concerned that the atmosphere was collapsing" and needed to get the information to the president, according to court documents.

Gonzalez faces charges of unlawfully entering a restricted building or grounds while carrying a deadly or dangerous weapon. He was carrying a knife when he entered the White House. The charge carries up to 10 years in prison.

After his arrest, officers found more than 800 rounds of ammunition, two hatchets and a machete in his car, Mudd told the judge.

Mudd said Gonzalez's "preoccupation with the White House and accumulation of large amounts of ammunition in apparently a short period of time renders him a danger to the president," and argued against Gonzalez being released on bond. Gonzalez was still in custody on Monday.

Deliberations in Gonzalez's case will continue in D.C. District court on October 1.

Securing White House is 'complicated business'

U.S. Homeland Security Secretary Jeh Johnson, who oversees the Secret Service, said in a statement that Americans should "not rush to judgment about the event and not second-guess the judgment of security officers who had only seconds to act."

Securing the White House is "complicated business," White House spokesman Josh Earnest said. Apart from being home to the president and his family, the building is a popular tourist destination and an office building.

Protests are often held at Lafayette Park, across from the White House.

Denis McDonough, Obama's chief of staff, and other White House officials met with the Secret Service on Monday, and Obama was briefed several times during the weekend, Earnest said.

"The president is going to leave it up to the professionals, the United States Secret Service, to determine the security posture that is necessary to both protect the first family that lives here, but also to ensure the White House remains the people's house," Earnest said.

The Secret Service has increased foot patrols and added surveillance, and it is also locking the front door to the White House when it is not being used by tour groups or events.

With files from CBC News and The Associated Press