More Web attacks hit, North Korea suspected

By Jack Kim

SEOUL (Reuters) - A fresh wave of cyber attacks that slowed U.S. and South Korean websites this week hit more targets Thursday, a Web security firm said, while the South's spy agency has said the hacking may be linked to North Korea.

The impact of the attacks, aimed so far at dozens of sites including the White House and the South's presidential office, was seen as negligible, experts said, but served as a reminder that Pyongyang has been planning for cyber warfare.

"The anticipated attack did take place, but considerable countermeasures were taken and it did act as a defence to some degree," an official at the online security firm Ahnlab said.

Some South Korean government websites, including the Defence Ministry and the National Intelligence Service, were affected. Access to some U.S. government sites, including the State and Defence Department, from South Korea appeared to be disabled.

In Washington, U.S. government officials said all federal websites were up and running and there was no impact from any new attacks Thursday.

The Pentagon said it had experienced an increase in cyber activity for about 24 to 48 hours after the July 4 holiday but the upswing had no significant effect on operations.

The Internet sites of some South Korean banks experienced a surge in access requests but a bank official said programs were run to disperse traffic and bring service back within an hour.

If the North was responsible, it would mark an escalation in tension already high from Pyongyang's nuclear test in May, a barrage of ballistic missiles in July and repeated taunts of long-time foes Seoul and Washington in its official media.