Director of the National Security Agency Keith Alexander said he doesn’t understand why “the system didn’t blink red” when Snowden left the U.S. in the first place. “It’s clearly an individual who’s betrayed the trust and confidence we had in him. This is an individual who is not acting, in my opinion, with noble intent.” | John Shinkle/POLITICO NSA chief: Snowden didn't act nobly

The director of the National Security Agency said on Sunday that he didn't understand how NSA leaker Edward Snowden left the United States without setting off warning signals.

"No, I don't," Gen. Keith Alexander said on ABC's "This Week," when asked whether he understood why "the system didn't blink red" when Snowden left the U.S. "It's clearly an individual who's betrayed the trust and confidence we had in him. This is an individual who is not acting, in my opinion, with noble intent."

His comments came amid news that Snowden, who was living in Hawaii and went to Hong Kong as the leaks stories broke, has since left and landed in Russia, despite U.S. hopes that he would fall into law enforcement custody.

When pressed as to how Snowden could have revealed details about classified national security programs, Alexander acknowledged that "the system didn't work."

"Well, this is a key issue that we've got to work our way through," he said. "Clearly the system did not work as it should have. He betrayed the trust and confidence we had in him. This is an individual with top secret clearance whose duty it was to administer these networks. He betrayed that confidence and stole some of our secrets."

Alexander said that officials are committed to preventing such leaks in the future, but said that ultimately, much responsibility lies with people entrusted with such information.

"We are now putting in place actions that would give us the ability to track our system administrators, what they're doing, what they're taking, a two-man rule," he said. "We've changed the passwords. But at the end of the day, we have to trust that our people are going to do the right thing. This is an extremely important mission defending our country.

"When they betray that trust, well, then we have to push it over to the Department of Justice and others for the appropriate action," he continued.

