A special train possibly belonging to North Korean leader Kim Jong Un was spotted this week at a resort town in the country, according to satellite images reviewed by a Washington-based North Korea monitoring project, amid conflicting reports about Kim’s health and whereabouts.

The monitoring project, 38 North, said in its report on Saturday that the train was parked at the “leadership station” in Wonsan on April 21 and April 23. The station is reserved for the use of the Kim family, it said.

Though the group said it was probably Kim Jong Un’s train. “The train’s presence does not prove the whereabouts of the North Korean leader or indicate anything about his health but it does lend weight to reports that Kim is staying at an elite area on the country’s eastern coast,” the report said.

Speculation about Kim’s health first arose due to his absence from the anniversary of the birthday of North Korea’s founding father and Kim’s grandfather, Kim Il Sung, on April 15.

North Korea’s state media last reported on Kim’s whereabouts when he presided over a meeting on April 11.

China has dispatched a team to North Korea including medical experts to advise on Kim Jong Un, according to three people familiar with the situation.