A third man from Birmingham has pleaded guilty to illegally killing sheep and lambs taken from farmers' fields.
Twelve reports of illegal butchery were made in Northamptonshire last year.
Voirel Manu, 39, changed his plea to guilty for conspiracy to steal in relation to the slaughter and butchery of livestock before his trial started at Northampton Crown Court.
Robert Iordan, 23, and Florin Nutu, 36, had already admitted to same offences last month.
Det Con Jamie Cooper, from Northamptonshire Police, said: "These crimes caused farmers a great deal of upset and anger last year and I'd like to thank them and the wider rural community for their support and patience during our investigation."
Iordan and Nutu, of Dunsink Road, near Villa Park in Birmingham, and Manu, of no fixed address but living in Birmingham, are due to be sentenced on Friday.