Government measures to get foot-and-mouth under control quickly look to have failed last night as a "second wave" of the disease spread through cattle.

It had been hoped that the nationwide ban on moving livestock, brought into force two weeks ago, would have helped win the battle against the virus.

The disease commonly has an incubation period of two weeks and it was argued that all cases should have shown up by now.

But such hopes, which had already looked unrealistic after 26 cases were recorded between Wednesday and Thursday, were finally dashed yesterday.

The Ministry of Agriculture yesterday confirmed there were 20 new cases of foot-and-mouth across the country - including one in County Durham at Thornley Village, near Fir Tree, Crook - bringing the total figure to 126.

Chief Veterinary Officer Jim Scudamore described the trend as a "second wave" and it was feared that the disease was still being spread by sheep which ministry officials had so far been unable to trace.

In particular, farmers who last month struck deals for sheep outside the official sales rings at Longtown market, near Carlisle in Cumbria - a known contact point for the disease, were again urged to come forward.

Such deals carried no paperwork, making successful tracings almost impossible.

Mr Scudamore said the disease was now threatening the lambing season, warning that the "type O" strain of the virus was especially deadly to lambs.

* The RSPCA has destroyed three billie goats at its Great Ayton animal rehoming centre, near Middlesbrough.

The goats, which were kept at the entrance to the centre, were considered at great risk from catching the virus.

The RSPCA feared that if the disease struck, it could be spread on the feet of hundreds of visitors who arrive at the centre each week.