A surveillance video released Thursday shows a guard leaving his post shortly before a man sneaked past the vacant post, shutting down a terminal at Newark Liberty International Airport Sunday.
Sunday evening's security breach caused massive delays after federal officials closed the terminal for six hours.
The video shows the guard leaving his podium for several seconds. The woman then comes from inside a secure, passengers-only area and motions to the man, who ducks under a rope. The couple embraces and walks arm-in-arm past the vacant podium.
The video was released at the insistence of New Jersey Sen. Frank Lautenberg.
The TSA agent apparently knew the man - who appeared to be a young Asian man wearing a tan suit - was a troublemaker.
The TSA agent can be seen approaching the man standing along the passenger exit lane and telling him to move away from the secure area. Then the TSA officer walks away from his post. He's gone for a least a minute, reports CBS News correspondent Byron Pitts.
At that point, the man in the tan jacket makes his move, slipping under the rope and joining arms with his female companion, who cleared security legally. Apparently the mystery man just to walk her to her gate, Pitts reports.
The TSA officer returns to his post but remains clueless about the security breech. It takes a bystander to alert the agent that there was a problem.
The tape comes from Continental Airlines' surveillance system, because the TSA camera .
"The worst part of it is we don't even know what his mission was. Was he bird dogging for a future incursion or was he an innocent guy trying to catch up with a friend and how did he know it was a critical place to be at a critical moment?" said Lautenberg on Thursday.
The breach caused major delays and grounded flights for six hours. The Transportation Security Administration said Monday that the man walked out of the airport 20 minutes later.
The security officer has been reassigned to non-screening duties during the TSA's investigation of the breach.
Lautenberg and fellow New Jersey Sen. Robert Menendez, who have both been highly critical of the actions taken by the TSA, say the security agency must continue its investigation and find the man immediately.
"Whatever reason he wanted to see her is not acceptable. That person should be found and prosecuted," said Menendez on Thursday. "Number one to understand fully what was his intention and number two, to insure that there is a message sent that there is a consequence to breaching security."
This was the latest TSA security lapse, but not the first. Just last month TSA's security manual for all airports checkpoints was .
Watch the surveillance video: