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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A "once-in-a-lifetime" music festival promising luxury and fine food has descended into chaos, leaving many ticket-holders stranded.
A fine start to the Bank Holiday weekend but some rain will arrive by Sunday.
A rapist has been given three life sentences for a vicious attack on an 81-year-old woman minutes after he sat next to her on a bus.