Dyfed Powys Police and the FSA will today begin interviewing the three men arrested on suspicion of offences under the fraud act.
The arrests follow a joint operation with the FSA at Farmbox Meats in Aberystwyth and the Peter Boddy Slaughterhouse in Todmorden, West Yorkshire.
Two men aged 64 and 42 were detained at Aberystwyth police station over night and a 63 year old man arrested in Yorkshire has today been transported to Aberystwyth.
Interviews with the three men are likely to continue through the day.
Meanwhile Dyfed Powys Police officers will maintain a presence at the site in Aberystwyth.
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It will be a bright start to Saturday, with some sunny spells. However, cloud and rain will reach the far west by late-afternoon.