South Korea's foreign ministry is asking authorities in China to give them access to a South Korean missionary detained in the northeast of the country.
The man, only identified by his family name Kim, was arrested on Thursday in the city of Yanji, near the North Korean border.
He's being held for five days on charges of violating immigration law.
An official from the foreign ministry said they also plan to offer legal and diplomatic support to the detained missionary.
Radio Free Asia reports that the man was among four Christian missionaries arrested by the Chinese authorities.
A source told RFA that one is Korean American and two are Chinese of Korean descent.