A Texas man was armed with a knife when he made it into the White House in an alarming security breach that has put the Secret Service under fire as Islamic State terrorists are calling for attacks on American soil.

“This was a very serious breach considering the ongoing threat from ISIS. I think that the Secret Service messed up seriously,” said Edith Flynn, professor emeritus at Northeastern University and a terrorism expert. “They’re going to have to have a serious review of their security measures. No one should be able to enter the White House the way this man did, whether they’re not with it mentally or otherwise.”

Officials had originally said that Omar J. Gonzalez, 42, of Copperas Cove, Texas, was unarmed when he scaled a fence near the north side of the White House complex shortly after 7 p.m. Friday and ran toward the front of the building, making it through the North Portico doors before being caught. But a law enforcement official who asked not to be identified yesterday said Gonzalez had a small folding knife and faces a weapons charge.

Less than 24 hours later in a second security breach, an unidentified man who was turned away from one of the White House gates yesterday afternoon returned a short time later in a vehicle and was arrested for unlawful entry after refusing to leave a security screening area.

The first family wasn’t at home during either incident.

Friday’s breach prompted the Secret Service to beef up security and call for a “comprehensive” review of their protocol, according to a statement issued yesterday. “The location of Gonzalez’s arrest is not acceptable,” it read.

Secret Service Director Julia Pierson “immediately ordered the Secret Service’s Office of Professional Responsibility to conduct a comprehensive after-action review of the incident.”

This isn’t the first time ?Secret Service agents have had to scramble to protect the White House.

• In October of last year, a Stamford, Conn., woman was shot dead by police after attempting to ram the White House gates and leading authorities on a high-speed chase.

• In 2009, Michaele and Tareq Salahi crashed President Obama’s first state dinner.

• In 1994, a 38-year-old Maryland man stole a small plane and flew it onto the White House’s South Lawn, where he crashed and died.

Flynn said the Secret Service can’t afford security lapses when ISIS is looking to pull off a terror attack against the U.S.

“Unfortunately, groups like ISIS are watching and they will continuously probe various security measures,” Flynn said.

“Ever since 9/11, particularly the attack on the Pentagon and the intended attack on Congress, those attempts have shown that these are the kinds of things where you can’t afford a lapse even for 60 seconds.”

The Associated press contributed to this report.