Last week, a mother was forced to barricade herself and her 14-month-old baby inside her home as thousands of mink swarmed over her isolated country house near a farm in Staffordshire, in the Midlands, which had been targeted by the animal activists.

Some 7,000 of the vicious predators, which are not native to the United Kingdom, were released from their cages.

Police have advised people living nearby to keep doors and windows closed and to keep children and pets indoors while teams of hunters try to trap the mink, which are desperate for food.

'These people are terrorists who have taken the law into their own hands. If they think this is the solution, they are very dangerous individuals,' said Len Kelsall, chairman of the British Fur Traders Association. 'The mink is a vicious animal when it is hungry.' Mink who have escaped from fur farms have established large feral populations throughout the British Isles so that they are now one of the most common carnivores in the country with hundreds routinely shot by gamekeepers and forest wardens.

Conservationists have compared the effect of releasing the mink, which were originally imported from North America, to pouring a tanker full of chemicals into a stream, but the activists are unrepentant. They are angry the Government has not made parliamentary time to pass legislation to close down the 15 mink farms left in the UK.

One Animal Liberation Front member warned there could be more attacks if legislation was not introduced during the next session. 'I would expect an escalation in extra-parliamentary animal rights activity because of the Government's broken promise on fur farming, hunting, vivisection and animal exports,' he said.

Mink have been raised on farms in the UK for the past 70 years, with pelts sold for about HK$130 each to manufacturers mostly in Russia and Hong Kong. A large farm may produce up to 60,000 a year, keeping the mink in conditions similar to battery hens.

Before winning last May's election the Labour Party pledged to outlaw the industry, following growing public opposition. But it has since delayed taking any action and has said it is unlikely to introduce legislation before 2001.

The issue of animal rights is never far from Britain's political agenda with the Government squeezed between pressure from the agricultural industry and animal welfare groups.

A number of issues from fox-hunting to transportation of farm animals and even importation of pets have been the subject of increasing public debate.

But while pressure from voters has led to farmers being forced to observe strict regulations designed to protect the welfare of their livestock, consumers are not always prepared to accept the necessary increase in prices.

British pig farmers this year faced a huge increase in costs after new regulations required them to raise their herds in more comfortable and expensive pens. But faced with having to pay more for their pork chops many shoppers have chosen to buy cheaper joints imported from elsewhere in Europe, where farmers do not face the same regulations.

The economic realities have forced the Government to reconsider many of the proposals backed by the less radical animal welfare groups.

But in one small area which attracted criticism from former Governor Chris Patten it has announced it will be taking steps which have won approval from animal lovers. Mr Patten has protested that quarantine regulations have prevented him from returning his two pet dogs, Whisky and Soda, to their home in the UK.

The Government has announced it will suspend the current six-month quarantine requirement for a new scheme which will rely on documentary proof animals have been immunised against rabies and other diseases.

Agriculture Minister Nick Brown is expected to outline the new proposals later this week, following pressure from the Royal Society for the Prevention of Cruelty to Animals and British expatriates. The new regulations will require special passports for pets and microchip implants similar to those used in Hong Kong.