N. Korea suspected in attacks on U.S. websites

North Korea may be behind a denial-of-service cyberattack that hit websites from the White House to the Secret Service, plus Treasury and State, according to South Korean sources.

The Korea Herald reported that the virus, which also affected Korean sites including the Defense and Foreign ministries, had been tracked to a house in eastern Seoul, according to the Cyber Terrorism Response Center of the National Police Agency.

Yonhap news agency reported, though, that South Korea's spy service believes North Korea or sympathizers were ultimately behind the attacks. The National Intelligence Service is to report its findings to a South Korean government committee on Thursday.

The intelligence agency released a statement Wednesday saying that the "elaborately planned" attacks appeared to originate from "a certain organization or state."

The cyberattacks come just days after North Korea staged a Fourth of July launch of seven ballistic missiles into the Sea of Japan, drawing a muted response from Washington and further discussions at the U.N. Security Council on Monday. President Obama said in a recent CBS interview that he doesn't "think that any war is imminent with North Korea."

Wednesday marked the 15th anniversary of the death of Kim Il-Sung, and a memorial ceremony in Pyongyang was used as another launching pad for verbal attacks against the U.S. and South Korea.

"We will sternly smash the U.S. imperialist forces and South Korea's puppet regime anti-unification plot," the country's second-in-charge, Kim Yong Nam, said on state television.

The virus slowed down or crashed more than two dozen sites Tuesday by overwhelming their traffic capacities.

Also targeted were the websites for the Transportation Department, the Federal Trade Commission, the Pentagon, Nasdaq, Homeland Security, The Washington Post and the National Security Agency. The presidential and National Assembly sites of South Korea were also disrupted.

Attempts to hack federal websites are nothing new, and the denial-of-service attacks hamper public access rather than compromise classified information. Yonhap reported that South Korea's Defense Security Command is subject to up to 95,000 hacking attempts per day.