What country did North Korea invade on June 25, 1950?

South Korea invade North Korea

Explanation:

At dawn on June 25, 1950 (June 24, in the United States and Europe), 90,000 communist troops of the North Korean People's Army invaded South Korea across the 38th parallel, catching the Republic of Korea's forces completely off guard and throwing them into a hasty southern retreat.

North Korea invaded South Korea on June 25, 1950

Explanation:

They caught the armed forces off guard, forcing them to retreat to the south. Shortly after, the U. N. demanded that North Korea immediately cease it's invasion of South Korea.