A 63-year-old man was also arrested at Peter Boddy Slaughterhouse in West Yorkshire, the other plant where operations were suspended on Tuesday in an investigation by the Food Standards Agency.
Dyfed-Powys Police has confirmed three people are being held on suspicion of offences under the Fraud Act.
They are being detained at Aberystwyth Police Station, where they will be interviewed jointly by the police and the FSA.
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A dull and damp night with mist and hill fog, with heavy downpours over the hills!
Darren Osborne from Pentwyn, Cardiff was arrested by police in the early hours of Monday after allegedly ramming his van into worshipers.
A landlord has been fined at Cardiff Magistrates Court after pleading guilty to 8 charges relating to a property in Albany Road, Cardiff.