Players of the gaming craze Pokemon Go have been involved in hundreds of police incidents since it was launched just last month, according to reports.
Gamers have been involved in robberies, driving offences and a mass brawl since the augmented reality game hit Britain's streets.
Some 290 incidents were recorded by forces across England and Wales since the smash hit game launched in the UK on July 13, according to data released to the BBC under the Freedom of Information Act.
Lancashire Constabulary logged 39 incidents - the highest figure from the 29 forces that provided data.
In Surrey, police were called out to reports of 30 people fighting after a Pokemon hunt turned into a brawl.
Officers in north Wales discovered a man with learning difficulties had invited children back to his home "as he had loads at his address".
Both Greater Manchester Police and the London's Met said Pokemon "lures" - which attract the creatures to the player - had been set up as robbers used the game to distract victims before snatching their mobile phones.
British Transport Police recorded two incidents of children trespassing on railways while playing the game, and several drivers have been spotted playing the game behind the wheel.
West Midlands Police referred to someone being "offered sexual favours" but provided no further detail.
While South Yorkshire Police said a Pokemon player had been punched and had their phone taken by three "unknown assailants".
And drivers have been flouting the laws of the road to play the game, it emerged.
Officers in Surrey discovered nine cars "parked across a junction" while looking for Pokemon.
Police in Devon were called to reports of a motorist driving down one-way streets and "stopping in the middle of the road playing Pokemon".
Pokemon Go uses a smartphone's GPS to create an augmented reality game in which players collect creatures known as Pokemon as they walk around the real world.
Gamers can visit locations known as Pokestops, which are usually local landmarks, where they can pick up free items to play the game.
Nintendo's stock skyrocketed following the success of the game, adding billions of pounds to the value of the company.
A spokesman for Niantic, which developed the game, said the company takes the issue of "player safety" seriously.
He told the BBC: "We encourage all people to be aware of their surroundings and to play alongside friends or family, especially when you're exploring unfamiliar places.
"Please remember to be safe and alert at all times, don't drive and play, abide by local laws and respect the locations you visit."
Lancashire Constabulary said Pokemon players should never trespass on private land or put themselves in any sort of risk for the sake of the game.
A force spokesman told the BBC: "People should avoid potentially dangerous locations that could make you vulnerable to injury or become a victim of crime.
"Never enter any body of water. Pokemon do not appear beyond the safety of the shoreline. And don't enter derelict structures, unlit footpaths or alleyways."