The Thai King's eldest daughter collapsed from a heart condition on Wednesday evening, Thailand's royal palace says.
Princess Bajrakitiyabha, the eldest daughter of King Vajiralongkorn, collapsed while training her dogs north-east of Bangkok, the palace said.
The 44-year-old was taken to a nearby hospital, then taken by helicopter to Bangkok, where she is being treated.
The palace described her condition last night as "stable to a certain extent".
Medical bulletins from the royal palace in Thailand are typically vague and cryptic, and from the single statement issued about Princess Bajrakitiyabha, it is difficult to gauge how serious her condition is, says the BBC's Jonathan Head in Bangkok.
Full article from BBC