A man who scaled a fence into the White House compound last Friday is a decorated Iraq veteran who had more than 800 rounds of ammunition in his car.
A court heard that Omar Gonzales had also been arrested in July with a sniper rifle and a map on which the executive mansion was marked.
The US Secret Service is carrying out an internal review as to how Gonzales managed to breach security and get so far before being stopped, as well as what measures to take to prevent such incidents happening again.
President Obama was not in the White House at the time, having already left for Camp David for the weekend.
Speaking on Monday he said he still has confidence in his protectors.
“The Secret Service does a great job. I’m grateful for the sacrifices they make on my behalf and on my family’s behalf.”
This is the latest lapse in security involving the Secret Service. The agency is reported to be considering expanding the security zone around the White House to keep the public further away.