Attila Foeldesi 45, is the subject of a European Arrest Warrant after being found guilty of offences of human trafficking and theft in Hungary.
He was sentenced to more than five-years in prison for the offences.
Officers have been conducting extensive enquiries to find him. It is believed that Attila Foeldesi, who is also known to use the name Foldesi, has been living in the Beeston area of Leeds and may have contacts across West Yorkshire the UK.
Anyone who has any information as to his whereabouts is asked to contact police via 101 quoting 13170561546.