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 decades-long ban on photography during official tours around the White House has been lifted, officials have announced.
Highs rising to the mid 30s across southeast England and well above average elsewhere in the UK.