Updated

North Korea has denied involvement in a cyberattack that shut down nearly 50,000 computers and servers at South Korean broadcasters and banks last month.

The General Staff of the Korean People's Army issued the denial Saturday through the official Korean Central News Agency. Seoul on Thursday said Pyongyang was responsible for the March 20 computer crash.

The denial comes as tension remains high on the Korean Peninsula. U.S. and South Korean officials say North Korea appears to be preparing to test-launch a mid-range missile that could fly as far as Guam.

The North has released a chain of warlike threats since Seoul and Washington began joint military drills last month. Pyongyang is also angry over new U.N. sanctions punishing it for its Feb. 12 nuclear test.