A computer is seen down after hacking at main office of broadcaster YTN in Seoul March 20, 2013. South Korean authorities were investigating a hacking attack that brought down the servers of three ... more 

A computer is seen down after hacking at main office of broadcaster YTN in Seoul March 20, 2013. South Korean authorities were investigating a hacking attack that brought down the servers of three broadcasters, including YTN, and two major banks on Wednesday, and the army raised its alert level due to concerns of North Korean involvement. REUTERS/Handout/YTN less