Britain started to kill tens of thousands of healthy sheep, goats and pigs on Friday in an effort to end the foot-and-mouth outbreak. It is predicted the mass slaughter could lead to the death of one million animals and is expected to last several weeks. On Sunday the number of foot-and-mouth cases in Great Britain stood at 322. Ben Gill, president of the National Farmers Union (NFU) which backs government plans, said any action that eradicated the disease from Britain's shores should be taken. "I'm not happy having to slaughter any animals, I'm distressed at the state we're in. But I have to recognise that if it means we can stop the spread of this disease, then this is an action we have to implement," Gill told the press. Under UK government plans, all sheep, goats and pigs within two miles of highly infected areas will be killed. The disease, which was first detected on February 21, has since spread to 256 locations in Britain.