By LAURA KING Associated Press Writer

LONDON (AP)--Black smoke from a flaming pyre of livestock carcasses drifted across a busy highway--a grim reminder for passing commuters of the growing toll of Britain's first outbreak of foot-and-mouth disease in two decades. More new cases were confirmed Monday.

Fears intensified that the highly contagious livestock ailment could spread to continental Europe. As a precaution, authorities in Germany began slaughtering animals that had been imported from Britain before the first cases of foot-and-mouth disease were discovered at a slaughterhouse a week ago.

Animals were killed Sunday and more were being slaughtered Monday in Germany's North Rhine-Westphalia state, the state agriculture minister Baerbel Hoehn said. Hoehn said imports of British livestock will remain banned for the time being.

Hopes of swiftly containing Britain's outbreak dimmed Sunday when, after a 24-hour lull, more new cases were confirmed at a farm in Devon, southwest of London. The farm had shipped sheep to Europe before an export ban took effect last week, raising fears that the disease could have already made its way into European herds.

European agriculture officials were meeting in Brussels on Monday to discuss the crisis.

In Essex county, northeast of London, where the first cases were found, the smell of burning animal carcasses hung in the air, and gray and black smoke drifted across the fields from two enormous piles of slaughtered pigs and cattle set ablaze Sunday night. It was the first mass incineration since the outbreak began.

Commuters on the busy M25 highway could see the billowing smoke rising from the two 100-yard-long piles. The carcasses were being burned to ash and buried in deep pits to try to prevent the spread of contagion.

So far, more than 2,000 animals have been slaughtered in a bid to halt the outbreak--a number that could be dwarfed if the disease cannot be checked soon. During a disastrous 1967 foot-and-mouth epidemic, Britain's worst, nearly half a million sheep, pigs and cattle had to be killed.

Foot-and-mouth disease is extremely easy to spread. The virus can be airborne, transmitted from one animal to another, contracted through contaminated feed, or carried by humans on boots, clothing and machinery.

Distraught over losses that are already mounting into the millions of dollars, farmers were besieging agriculture officials at all hours for advice on how to better protect their farms. They filled troughs with disinfectant, spread piles of disinfected straw across roads leading to their land, and anxiously watched their herds for the telltale blisters on the mouth and feet.

In a nation of animal lovers, wholesale slaughter of herds and burning carcasses--considered the only way to halt the virulent infection--caused emotional distress to many.

``It has been quite traumatic seeing ... all the dead animals,'' said Sue Scott, who lives only a few hundred yards from one of the carcass bonfires. ``It was very sad.''

So far, the disease has been found at nine sites, and animals at hundreds of farms and slaughterhouses were being tested. Government veterinarians were working around the clock processing test results.

The outbreak was making increasing inroads into daily life. Tight travel restrictions have been clamped on sites suspected of harboring the disease. In Northumberland in northern England, one of the affected areas, two schools were closing indefinitely _ teachers who live on farms have been told not to go to work. Another school was closed near the outbreak in Devon.

The disease affects only cloven-hoofed animals, but others can carry the virus. Horse racing officials are considering calling a halt to races, as they did during the 1967 outbreak. A safari park in Bedfordshire closed down. The Royal Society for the Protection of Birds shut its nature reserves.