Story highlights Canadian pastor Hyeon Soo Lim has been detained in North Korea since 2015

North Korea hasn't confirmed whether the Canadian envoy's visit is related to Lim

(CNN) A Canadian government envoy, Daniel Jean, national security adviser to Canadian Prime Minister Justin Trudeau, and his party arrived in Pyongyang, the state-run Korean Central News Agency reported. It gave no further details about why the Canadian official was there.

Canadian pastor Hyeon Soo Lim has been detained in North Korea for about 2½ years. The 62-year-old's health has deteriorated while in North Korean custody, and the pastor has experienced "dramatic" weight loss, family spokeswoman Lisa Pak said.

In letters to family, friends, and members of his church in Mississauga, Ontario, Lim has complained of stomach pain and high blood pressure.

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The Swedish Embassy in Pyongyang has served as an intermediary for Lim, as they do with other prisoners from countries with no formal diplomatic relations with North Korea. This has included passing letters, and also blood pressure medication, according to the Lim family.

Lim's family had stepped up calls for his release since the death of American university student Otto Warmbier in June.

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