Computer hackers have attacked government websites in South Korea, taking them out of service on the anniversary of the start of the 1950-53 Korean War.
A government statement said the identity of the hackers was not known.
The incident came on the anniversary of the start of the 1950-53 Korean War, which divided the Korean peninsula.
The website for the office for Government Policy Co-ordination and some media servers were also said to be affected by the attack.
The BBC reports messages praising North Korean leader Kim Jong-un and claiming that Anonymous was responsible were left on the hacked websites.
A number of North Korean websites also went offline on Tuesday morning and appeared to have been targeted by hackers.
The Yonhap news agency reported these included the websites of the Korean Central News Agency, and the Rodong Sinmun newspaper.
The BBC reports South Korea has raised its cyber alert level, and asked citizens to review their internet security.
On 20 March, cyber attacks on six South Korean banks and broadcasters affected 32,000 computers and disrupted banking services.
