(Adds details on case, quotes from statement)
SEATTLE, Oct 10 (Reuters) - The mother of an imprisoned American missionary and tour operator has arrived in North Korea to visit her ailing son, who was sentenced to 15 years of hard labor in May on charges of state subversion, his family said on Thursday.
The family of Kenneth Bae said that Myunghee Bae expected to be in North Korea for about five days for a trip in which she aimed "to encourage her son," who has diabetes and was in ill health.
"I don't really know what to expect for my trip. All I know is that I want to see my son," Bae's mother said in a statement in which she also expressed gratitude to Pyongyang for allowing the visit.
Bae, 45, was detained last November as he led a tour group through the northern region of the country. His sentencing came amid acrimonious relations between Pyongyang and Washington over the reclusive state's nuclear program.
In sentencing Bae, who has acknowledged being a missionary and has said he conducted religious services in the North, the court said he used his tourism business to form groups aimed at overthrowing the government.
The family said that Bae's health has deteriorated during his detention and that he was hospitalized two months ago and had lost a significant amount of weight.
Bae, a naturalized U.S. citizen born in South Korea who moved to the United States with his family in 1985, has spent much of the last seven years in China where he started a business leading tour groups into the northern region of North Korea, according to his sister. (Reporting by Eric Johnson; writing by Cynthia Johnston; editing by Jackie Frank)