LONDON (AP) — One of four lynx thought to have been released illegally in the Scottish Highlands has died within hours after it was captured, wildlife authorities said Saturday.

The medium-sized wildcats extinct in Scotland for hundreds of years were spotted in the snowy Cairngorms National Park this week, raising concerns that a private breeder had illegally released the predators into the wild. The lynx that died was one of a pair captured Friday.

“This unfortunate development just serves to further demonstrate the folly of abandoning these amazing animals in the wild, with no preparation or real concern for their welfare,’’ said Helen Senn, head of conservation at the Royal Zoological Society of Scotland. “We can only imagine the stress that all four of the recovered lynx must have experienced after being thrust into an entirely new and extremely harsh environment to fend for themselves.”

The sighting and capture of the lynx comes as some environmental activists seek to reintroduce lynx as a way to control the burgeoning deer population and highlight Scotland’s commitment to wildlife diversity.

Police are still investigating the incident and have released no information about possible suspects. Wildlife experts have speculated that the cats were released either by someone who took matters into their own hands because they were frustrated by the slow process of securing government approval or an opponent who wanted to create problems that would block the reintroduction effort.

A Conservative lawmaker for the area, Edward Mountain, said the second capture of lynx suggested “a concerted approach to illegally reintroduce lynx.’’

“These animals cannot magically appear, and the authorities should be tackling this wildlife crime with an absolute focus of finding out who is responsible,’’ he said.