Senior detectives had spent almost a year planning a huge operation to take down Jamaican drug barons and smash a multi-million pound crack cocaine network.

Four hundred officers, some armed, gathered at 5am across the country ready to smash their way into several addresses in London, West Midlands, North Yorkshire, County Durham, Northumbria, Middlesbrough, Stockton and Hartlepool.

In the early light of dawn yesterday morning several of them quietly made their way to a nondescript house in Kensington Street, Middlesbrough.

Using a battering ram officers in protective clothing then smashed in the door and stood back as their colleagues stormed in screaming “police, police”.

They flooded into every room, ready to stifle trouble before it began.

But instead of finding a hardened criminal inside the group of officers came across Betty Keen, an 80-year-old great-grandmother, cowering in her bed.

Mrs Keen, who has lived in the address trouble-free for 60 years, has eight sons, five daughters, and 55 grandchildren and great-grandchildren. She lives with one of her daughters, Sandra, 42.

Mrs Keen, told Times Online: "There must about four or five of them in the bedroom. I said 'What the hell are you doing in here, now get out' and I shook my fist at them. They said they were making inquiries about the house.

"It was very shocking, I am on medication. They wouldn't let me use the phone and it was only when my two grandaughters walked past the house and saw the door bashed in that my family knew what had happened."

Mrs Keen and her daugher were kept in their separate bedrooms for almost an hour.

Police have now apologised to Mrs Keen, given her a bunch of flowers and repaired the door of the house.

Despite the police peace-offering the pensioner’s family want to know why the house was targeted and plan to lodge an official complaint.

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