The White House has kept silent on who could be behind the recent hacking of that breached President Obama's email correspondence.

Senior American officials briefed regarding the situation have raised concerns about the depth of the hacking incident that could have exposed vital information regarding the president's schedules and even some notes and correspondence on foreign policy, the New York Times reported. 

The New York Times and ABC News sources said that Russian hackers could be behind the recent cyber attack on the White House.

In a recent address to Stanford University, Defense Secretary Ash Carter said that this hack is quite similar in nature to the recent information breach at the Pentagon. He said that the unclassified networks of the Department of Defense had detected Russian hackers accessing the agency's networks.

"They'd discovered an old vulnerability in one of our legacy networks that hadn't been patched. The cyber threat against U.S. interests is increasing in severity and sophistication," Carter said.

However, political analyst Justin Raimondo, writing on Libertarian website AntiWar.com, said these hacking incidents could be traced to the cyber security bills now being pushed in Congress.