Russia has arrested a South Korean man on suspicion of espionage.
South Korean media reported on Tuesday that the man was a missionary who supported North Korean laborers in Russia's Far East.
This is the first time a South Korean citizen has been arrested in Russia over alleged spying.
Espionage carries a maximum jail term of 20 years in Russia.
What else do we know about the spying allegations?
Russian state news agency TASS reported on Monday that the man had been detained in the far eastern city of Vladivostok and was transferred to Moscow as part of investigations.
The agency did not provide further details on the nature of the espionage, saying that the case was "top secret."
TASS described the man as a "deeply religious" person who was also registered as the founder of a travel company based in Vladivostok.
South Korean news agency Yonhap reported that the man was involved in helping North Koreans in Russia's Far East defect.
South Korea's Foreign Ministry said that its consulate had been providing the man with assistance since it became aware of the arrest.
A spokesperson told reporters that Seoul was communicating with Russia for the safe return of its national.
The ministry said the case was subject to an ongoing investigation and declined to give more information.
The Kremlin considers South Korea to be an "unfriendly" country, as Seoul has imposed sanctions on Russia alongside Western allies over Moscow's invasion of Ukraine.
Russia maintains good relations with Pyongyang. North Korean leader Kim Jong Un visited his Russian counterpart, Vladimir Putin, last year and declared that bilateral ties with Moscow were his country's "number one priority."
Washington says that Pyongyang is providing Moscow with munitions for use in the war in Ukraine, a claim denied by both Russia and North Korea.
