The US Holocaust Memorial Museum has asked visitors to stop playing an immersive video game which allows users to “catch monsters” while walking around its exhibitions.

Pokémon Go is an “augmented reality” smartphone game in which users try to trap fictional fighting animals like Charizard and Pikachu.

Players point their phone cameras at whatever is in front of them and the monsters pop up within the scene that is filmed.

This means that some gamers playing Pokémon Go at the US Holocaust Memorial Museum would have seen the monsters appear among exhibitions about concentration camps and Kristallnacht.

Reports indicate that players have also been collecting Pokémon characters at Auschwitz. The game’s slogan is “Gotta catch ‘em all”.

As users can place Pokémon at any location, some have put poisonous, gas-breathing monster “Koffing” in the museum and posted pictures of it on social media.

Many landmarks have become hubs of activity after the game was released this week and exploded in popularity, but the museum in Washington DC is especially popular.

The museum contains three ‘PokéStops’, or places where players can pick up special items.

Andrew Hollinger, communications director for the museum, said: “Playing Pokémon Go in a memorial dedicated to the victims of Nazism is extremely inappropriate.

“We are attempting to have the museum removed from the game. The museum encourages visitors to use their phones to share and engage with museum content while here.

“Technology can be an important learning tool, but this game falls far outside of our educational and memorial mission.”

It is understood that PokéStops locations were brought over from another game produced by the same company, US developer Niantic Labs.

Niantic has not responded to a request for comment.

Pawel Sawicki, an Auschwitz Memorial press officer, said: "Allowing such games to be active on the site of Auschwitz Memorial is disrespectful to the memory of the victims of the German Nazi concentration and extermination camp and it is clearly inappropriate.

"The authentic ground of the former camp is a place of commemoration of all the people who suffered, were dehumanised and murdered here – Jews, Poles, Roma, Soviet POWs and others.

"We ask producers of such games to exclude the site of the Auschwitz Memorial and similar sensitive sites – now and in the future."