Commuters have been warned about the dangers of playing Pokémon Go at train stations. The BBC's Tom Edwards tweeted a photo of a sign urging players to concentrate on where they are walking when playing the game. Another has been spotted at Oxford train station. The Network Rail notice also reminds commuters it is ‘illegal and very dangerous’ to trespass on a railway.

“Enjoying Pokémon Go? Please consider the following,” the Oxford sign said. “Remember to stop, look and listen when approaching the railway.

Concentrate - it's easy to get distracted by your phone, music or by catching Pokémon. “It is illegal and very dangerous to trespass on a railway - don't risk it for a game.”

Meanwhile, as the Pokemon Go craze hits Japan, reports of robberies, traffic accidents and other mishaps abroad already have the government worried. (Read our guides to gyms, eggs and pokemon items.) Yoshihide Suga, Chief Cabinet Secretary, said that the government wanted players to follow guidelines issued by a national center for incident readiness and cybersecurity. The UK coastguard has also warned eager Pokémon trainers not to venture out on to the open water after crews were called out in the early hours of the morning to investigate a group of teenagers crossing a marina.

HM Coastguard senior coastal operations officer Danny Jameson said: “We know that many people are enjoying Pokémon Go across the UK and we wouldn’t want to spoil that fun. “However, we would ask people to use a little common sense and not to take risks while looking for Pokémon. The incident this morning shows that risk taking can put not only you in danger but also the rescue services who have to come to your aid.” Meanwhile, a Pokémon Go master has become the first player to catch 'em all. While a player searching for Pokémon at 3am has revealed how he was caught up in a 'drug deal' mix-up. Here are 12 awkward places Pokémon really shouldn't have turned up.