A former Chester Hammond School drama student found himself surrounded by armed police after neighbours mistook a rehearsal for a real-life emergency situation.

Joel Harper-Jackson, 23, who is now an actor in the West End, was at home in south London last week helping his 25-year-old housemate Simon Gordon rehearse a scene for an upcoming audition for the Carole King musical Beautiful, before the pair sat down to watch television.

But their peaceful day was interrupted when they were suddenly confronted by five police officers brandishing assault rifles and riot shields demanding to know how many people were inside their home.

Some officers were even hiding outside in the garden and in the street, but luckily after the actors explained they were just rehearsing, the police realised their mistake and left.

Mr Harper-Jackson, who left the Hammond School in 2013, told the national press: “At first when we heard a really loud bang on the door we thought it must have been our other housemate and she’d forgotten the keys, but it was a load of riot police.

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“We got this abrupt knock at the door and there were five men with shields. I just thought, ‘what on earth is happening?’! They said they’d had a report of a firearm on the premises and Simon pleading for his life,” he added.

“I told them, ‘We’re just actors’. We were just rehearsing for an audition with the window open. You could just see the guy’s face drop and he turned his back and said to his colleague, ‘they’re actors, they’ve been practising for an audition’.

“And then it was all over in five minutes. They thanked us for our time and said an officer would come round to talk to us and we all ended up laughing about the ridiculousness of the situation.”

Julia Edwards, the Hammond School’s marketing manager, said: “We were amazed to hear the story, but not surprised that Joel gave such a great performance.”