Police arrested the men after it emerged a significant amount of horse meat containing the painkiller "bute" could have been entering the food chain for some time.
Authorities in Britain and France are trying to trace the carcasses of six horses contaminated with bute - which were slaughtered in a UK abattoir and may have entered the human food chain across the Channel.
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Warming up over the next few days. Mostly dry in the south, rain at times in the north.
Grace Mugabe, the wife of Zimbabwean president Robert Mugabe, has returned home from Johannesburg.