Several South Korean websites have been hit in a targeted cyber attack.
According to the Associated Press and media reports, the websites of 29 government and other agencies have come under attack with distributed denial-of-service (DDoS) attacks initially having been expected to hit up to 40 websites.
The South Korean websites hit included the presidential Blue House, the US forces, the military Joint Chiefs of Staff, the ministries of foreign affairs, defence and unification, parliament and the tax office.
The website of South Korean IT security company AhnLab warned visitors that DDoS attacks had been aimed at its domestic site and system damage caused by malicious code had been discovered.
It is reported that the incident began at 10:00am (1am GMT) and the South Korean government has said it is working closely with internet security agencies and others to deal with the problem.
An official from the presidential office told BBC News that ‘there was a DDoS attack, but no damage was done'.
Back in July 2009, attacks against South Korea and the United States were blamed on North Korea. In that instance, there were no immediate reports of financial damage or data breaches and the alleged attacks appeared to aim to paralyse websites.