SEOUL, South Korea - A computer security company says an additional wave of cyber attacks is expected to hit major South Korean websites later Thursday.

The Seoul-based antivirus software developer Ahnlab says it analyzed a virus program that has sent floods of Internet traffic to paralyze major South Korean and U.S. websites over the past days.

Spokeswoman Hwang Mi-kyung says the company found that the virus will trigger a new attack in South Korea from 6 p.m. (0900 GMT) Thursday.

She says the new attack will target seven websites, including those of a government security agency, Kookmin Bank and the Chosun Ilbo newspaper.

South Korea's intelligence authorities suspect North Korea of spreading the virus program. Hwang says her company has not found where the cyber attacks originated.