Eight sheep from the first flock brought into the Cooley area in Co Louth, following the foot-and-mouth outbreak, died of pneumonia last week.
According to farmers in the area who are unhappy with the compensation offered by the Department of Agriculture, the deaths of the sheep bought in Wicklow highlight the need for careful selection of animals for the Cooley flock. The Northern Ireland ban on marts, sales and exports was lifted yesterday. The Republic still bans imports.
Meanwhile, British authorities increased vigilance around infected areas over reports that infected sheep and blood had been offered to farmers so they could claim compensation.
Police in Wales started the investigations after a retired farmer, Mr Alan Thomas, discovered a camping light, container and gloves near Crick howell, close to a cluster of foot-and-mouth cases. Mr Thomas said he believed someone was spreading foot-and-mouth. "The container and gloves didn't walk there. Someone must have put them there," he said.
A farmer in Pembrokeshire also claimed a man had offered to sell her a sheep infected with foot-and-mouth for £2,000. Ms Nuala Preston, of Trefoel Stud Farm, received a telephone call from a man offering to sell infected sheep so she could spread the disease in her flock and claim compensation.
She said she was "horrified and angered" by the man's approach but thought some desperate farmers might be tempted by his offer.
Foot-and-mouth disease has been found in samples taken from a further 2,000 sheep tested in Wales. At the weekend 4,000 sheep in the mountainous Brecon Beacons area were culled after testing positive, and 4,000 more sheep are to be tested in Wales.