"The damage that these revelations incur are huge," James Clapper, Director of National Intelligence, told the NBC news.
"The NSA (National Security Agency) has filed a crimes report on this already," he said.
Clapper's remarks came as Edward Snowden, 29, who is now in Hong Kong told The Guardian and other news outlets that he leaked the classified information because he was not comfortable with this kind of phone and internet tapping.
"Booz Allen can confirm that Edward Snowden, 29, has been an employee of our firm for less than 3 months, assigned to a team in Hawaii," a statement from the firm said.
"News reports that this individual has claimed to have leaked classified information are shocking, and if accurate, this action represents a grave violation of the code of conduct and core values of our firm. We will work closely with our clients and authorities in their investigation of this matter," the firm said.
"This person is dangerous to the country. I think there's real questions as to why he left the CIA," King said.
"The fact that he's in China right now, or in Hong Kong, which is a sub-state of China, and he knows where our intelligence assets are, or our intelligence agents are around the world, and the fact that he has allowed our enemy to know what our sources and methods are is extremely, extremely dangerous," he said.
"I believe he should be prosecuted to the fullest extent of the law. I consider him right now to be a defector," King told the CNN.
"We should begin extradition proceedings as quickly as possible. That's going to be somewhat confusing with Hong Kong. It's a sub-state of China, but we do have an extradition treaty with Hong Kong. My concern is that in the meantime, China could be holding him and trying to get information out of him as to what he knows regarding our assets around the world," King added.
