By Evan Perez and Shimon Prokupecz, CNN
Updated 7:06 PM ET, Tue April 7, 2015

The State Department computer system has been bedeviled by signs that despite efforts to lock them out, the Russian hackers have been able to reenter the system. One official says the Russian hackers have “owned” the State Department system for months and it is not clear the hackers have been fully eradicated from the system.

As in many hacks, investigators believe the White House intrusion began with a phishing email that was launched using a State Department email account that the hackers had taken over, according to the U.S. officials.

Director of National Intelligence James Clapper, in a speech at an FBI cyberconference in January, warned government officials and private businesses to teach employees what “spear phishing” looks like.

“So many times, the Chinese and others get access to our systems just by pretending to be someone else and then asking for access, and someone gives it to them,” Clapper said.

The ferocity of the Russian intrusions in recent months caught U.S. officials by surprise, leading to a reassessment of the cybersecurity threat as the U.S. and Russia increasingly confront each other over issues ranging from the Russian aggression in Ukraine to the U.S. military operations in Syria.

https://www.cnn.com/2015/04/07/politics/how-russians-hacked-the-wh/index.html