South Korean government issued a travel warning to Russia Thursday, following attacks on South Korean students there.

The move, could seriously undermine Russia's reputation as a tourist destination in the international community, Yonhap news agency cited ministry officials as saying.

The move comes after a 29-year-old South Korean student, identified only by his surname Shim, was attacked while on his way home from a shopping mall in the Russian capital on Sunday.

The assailant, who wore a white face mask, waited until the victim parted from his friends before stabbing him in the neck, according to officials from the South Korean embassy in Moscow, who cited eye witnesses. The suspect immediately fled the scene.

The incident came about three weeks after another South Korean student in the Siberian city of Barnaul, capital of the Altai region, was stabbed to death in what was believed to be a racially motivated crime by three Russian youths. Seoul has repeatedly requested Russia to help prevent the recurrence of such crimes.

But cases have continued, though they are not on a quick rise, according to ministry officials.

"The government again asked the central government of Russia and police authorities in local governments around Russia to take measures to prevent such incidents.

"They, of course, promised to actively cooperate, but we are trying to make sure such cooperation will actually take place," the ministry spokesman said.

The local police in Moscow were earlier said to believe the latest attack on the South Korean student, too, may have been racially motivated as it bore similarity to crimes carried out by Russian skinheads in the area.

Shim, now in critical conditions, went to Russia six years ago and is currently enrolled at a cinema college in Moscow.