Over the weekend Pokémon Go players got excited when legendary bird Articuno was spotted at a US gym. It seems however, that instances of the bird and other legendaries Zapdos and Moltres appearing in the game have been either a mistake or an act of hacking the game.

As a result, developer Niantic will be taking the legendary birds away from players who have them. In a statement to IGN a representative said: "We recently noticed that a few legendary Pokémon got into a few accounts when they shouldn't have.

"To preserve the game's integrity and as a measure of fairness, we have rectified the situation and revoked the legendary Pokémon from the Trainers' accounts."

Niantic also attempted to clarify the validity of the Articuno's appearance in the game, which had been questioned since evidence first surfaced. The owners of the legendary claimed it was gifted to them by Niantic, but the developer told Geek.com that was not the case.

"[The Articuno] was not from Niantic," a spokesperson said. "It's either a spoof or someone hacked the game." This was before they revealed plans to take the legendary Pokémon away from players, confirming the evidence was not doctored or faked.

Niantic's reaction to the appearance of these Pokémon implies that they will only become officially available for players to capture at a later, unspecified date, when the developer decides. This could be a special event or just a general release.

Roughly one month on from the free-to-play game's gradual worldwide release, excitement around the game does not appear to be dying down. The game uses location data and augmented reality techniques to populate the world with the original 151 Pokémon which players then have to find and capture.

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