David Jackson

USA TODAY

The White House is confirming cyber attacks on unclassified computer networks, and people are pointing the finger of suspicion at Russia.

"The White House has detected some activity of concern on the White House network," said spokesman Josh Earnest, and is seeking to learn the source of hack attacks.

While security firms have accused Russia of involvement in similar attacks, Earnest said it would be "unwise" for him to speculate on culprits because an investigation is ongoing.

There is no evidence that hackers breached classified files, administration officials said.

"Our computers and systems have not been damaged, though some elements of the unclassified network have been affected," the White House said. "The temporary outages and loss of connectivity for our users is solely the result of measures we have taken to defend our networks."

At least one suspect is being discussed in the public domain.

From The Washington Post: "Recent reports by security firms have identified cyber-­espionage campaigns by Russian hackers thought to be working for the government. Targets have included NATO, the Ukrainian government and U.S. defense contractors. Russia is regarded by U.S. officials as being in the top tier of states with cyber-capabilities."

In recent weeks, White House officials have said that computer systems have been down, and e-mail has been slow. On Oct. 19, the White House e-mailed one statement through an alternate route, saying it was "due to system delays."

Earnest said the situation has ted some "inconveniences," but did not affect the work of the White House staff.

Information analysts said they were not surprised by the hack attack on the White House, and warned that all governments need to be on guard.

"Foreign government-sponsored hackers are a very real threat to public and private sector IT networks," said Gerry Grealish of the cloud security provider Perspecsys. "Today's cyber attacks are better funded, more aggressive and sophisticated, and can come from a myriad of external and internal sources."

Ben FitzGerald, with the Center for a New American Security in Washington, D.C., said governments can expect to be cyber-attacked. Security assessments, he said, depend on "how quickly intrusions are detected and mitigated, rather than whether or not they occur."

FitzGerald, who directs the center's Technology and National Security Program, said he is more concerned by reports that the administration was tipped off to the attack by an ally.

"How does an ally figure that out?" he said. "What were they monitoring that we weren't?"

One Republican lawmaker -- Sen. Tom Coburn of Oklahoma -- said the White House should have first notified Congress about the breach.

"I have pressed the administration to share details about what has happened and how the attack succeeded," Coburn said. "I have yet to receive satisfactory answers. Let us seize this opportunity to work together to protect against this very serious threat to our national security and economy."