South Korea's decision to officially classify Russia as a dangerous place for its nationals to travel to is "groundless," a source in the Russian Foreign Ministry told RIA Novosti on Friday.

Seoul issued a temporary travel advisory to its nationals after one South Korean student was killed and another injured in separate incidents in Moscow and south Siberia this month.

The Travel-Alert Level One warning lasts from March 11 until May 31. The Yonhap news agency said, citing officials from the South Korean Foreign Ministry, that the warning was in part intended to protect South Koreans from possible race-hate attacks on April 20, the anniversary of Adolf Hitler's birth.

The date frequently sees an increase in racially-motivated crimes in Russia.

However, a source in the Russian Foreign Ministry played down South Korea's concerns saying that "the decision is groundless." He added that an investigation was underway into the attacks.

A masked assailant attacked a South Korean student last Sunday in the Russian capital. The student was hospitalized after the attack and remains in a critical condition. Three weeks before that a group of young people stabbed to death another South Korean national in Barnaul, the capital of the Altai Territory.

Russia has seen a wave of racially motivated crimes since the collapse of the Soviet Union in 1991. Routine attacks by skinheads and gangs of youths on foreigners and people with non-Slavic features are a regular occurrence in Moscow and St. Petersburg, as well as the city of Voronezh, which hosts many foreign university students.

MOSCOW, March 12 (RIA Novosti)