At a training site in Russia, the five North Korean soldiers had grins on their faces and guns in their hands. Then they began singing a cappella, belting out a Soviet-era song called “Katyusha" about a young woman bidding farewell to soldiers—in translated Korean-language lyrics.

North Korean leader Kim Jong Un made a rare visit to Russia's embassy in Pyongyang with his daughter on Friday and reaffirmed "the invincible alliance" between the two countries, while Russia's leader greeted North Korean generals in Moscow.

North Korea's deployment of thousands of troops helped Russia push back a Ukrainian incursion. Read more at straitstimes.com. Read more at straitstimes.com.