Four armed teenagers used the game Pokémon Go to lure victims into a trap before robbing them.
The augmented reality app, released in the US on 6 July, uses gamers' locations to guide them towards virtual characters on their smartphones. The game has been so popular that high demand has caused the servers running it to crash.
According to Missouri police, a group of teenagers used the game to place a “beacon” at a car park. In the Pokémon app, a beacon attracts players towards a "Pokéstop", where they can restock on virtual items needed to play the game.
After placing the beacon, police say the suspects waited for their unsuspecting victims to arrive and then robbed them.
Police were called to a robbery close to a petrol station at 2am on Sunday. The four teenagers were arrested when they were spotted in a black BMW.
Phil Hardin, a police sergeant from O'Fallon, Missouri, said: “All of the elements of a robbery were there, so that part was easy, but the more in-depth discussion that followed was like, ‘What?’ You really can’t make this stuff up.”
“Younger, geeky officers” had to explain some of the circumstances of the robbery to their older colleagues, Mr Hardin joked to local press.
After carrying out searches, police found a handgun. Officers believe the suspects, aged between 16 and 18, might be responsible for almost a dozen robberies.
Speaking to gaming news site Motherboard, Sergeant Bill Stringer said police were becoming aware the game could be used for sinister purposes.
“As far as we can tell you can put a Pokébeacon or something on [the app] and it attracts Pokémans [sic] and alerts other players to your location," he said.
“It’s a great app for getting people off the couch, but it can be used for nefarious reasons, also."
In a statement, O’Fallon Missouri Police department warned of the dangers of playing the Pokémon game.
“If you use this app or have children that do we ask you to please use caution when alerting strangers of your future location,” they said.
Three of the group accused of armed robbery, aged 17 and 18, were changed with first-degree robbery before their bond was set at $100,000 cash. The other suspect is a minor and has been transferred to a juvenile justice centre.
Outside the gaming world, the app gained public attention after it guided a 19-year-old in Wyoming to a man's corpse.
