Two brothers told a jury they were shocked to discover drugs were being produced in a barn at their family home.

Russell and Adam Hoare were giving evidence during the fifth week of a trial at Lewes Crown Court.

Russell, 20, and Adam, 19, both of Princes Plain, Bromley, their father Kevin Hoare, 46, of Bugsell Mill Oast, Hurst Green, near Robertsbridge, his girlfriend Tracey Thaker, 35, of Vicarage Way, Hurst Green, and handyman Alan Smith, 52, of Frewin Close, St Leonards, have all denied conspiracy to produce a controlled drug.

Kevin Hoare, who runs a company making glass scientific products, and Graham Pierce, 41, of Greyswood Street, Streatham, have denied conspiracy to supply a controlled drug.

The court has heard how police found a drugs factory when they raided a barn at the isolated Bugsell Mill Oast in July last year.

Police estimated £20 million worth of amphetamine sulphate, known as speed, had been produced in a laboratory set up in the barn.

The two brothers told the court they believed their father's explanation that the barn was being rented out to a man who was making a medical compound.

Russell Hoare told the jury he was curious what the compound was but he had dismissed any possibility it was illegal drugs because his father was against drugs.

He said: "My dad has always been strongly against drugs. We all have."

Russell Hoare said the smell from the laboratory was so strong it made him feel unwell.

He said: "My dad told me it was for research."

Adam Hoare, 19, said: "I never believed it was drugs. My dad said it was to do with radiology. It didn't surprise me because scientific medical equipment was Dad's business."

He said on two occasions he had been asked to carry out a task in the barn, such as take something off a hot plate and put it in the freezer.

Earlier their father had told the jury he rented the barn to a business associate for £500 who was making a chemical compound which could be used to make medicine to treat cancer and other diseases.

He said after a while he started to help out with the chemical process.

Kevin Hoare, who has no previous convictions, said he had no idea he was helping to make illegal drugs.

The trial continues.