07/16/2013 02:22 EDT | Updated 09/14/2013 05:12 EDT

South Korea says North Korea behind last month's cyberattacks

SEOUL, South Korea - South Korean investigators say North Korea carried out cyberattacks on the websites of South Korean media companies and the president and prime minister's offices last month.

The attacks came on the June 25th Korean War anniversary.

South Korea's Ministry of Science says it's blaming North Korea based on analysis of codes, Internet addresses and personal computers used to launch the attacks.

The government-led team of investigators say the online assaults were planned for several months.

The attackers hacked file-sharing websites in South Korea to find security weaknesses.