Craig Smith, 49, is wanted on recall to prison for an incident on August 20 2016, where a firearm was alleged to have been seen at an address in Leeds.
He was released on licence in September 2015 after serving part of a sentence for drugs offences and driving without insurance.
The police appeal was featured on today’s (June 20) Crimewatch Roadshow on BBC1.
He is described as being about 5ft 10 in tall and of heavy build.
He has links across Leeds and to North Yorkshire and may be sleeping rough.
He is known to frequent the east coast of North Yorkshire, particularly Scarborough and Whitby, as well as Humberside.
Detective Chief Inspector Nicola Bryar, of West Yorkshire Police’s Homicide and Major Enquiry Team, said: “Our officers have made extensive enquiries to trace Craig Smith, who is wanted for questioning in relation to these very serious offences.
“We remain committed to securing his arrest in relation to these matters and hope that today’s television appeal will bring some new information on his whereabouts, which will help to progress this investigation.
“While he could be anywhere in the country, we are aware he has been known to frequent the east coast of North Yorkshire, particularly Scarborough and Whitby, and I would like to appeal specifically to people in those areas who may have seen him or who have any information on his whereabouts.
"Although we do not believe he presents a threat to the wider community anyone who sees him should not approach him and contact the police immediately on 999.
“Information can also be reported anonymously to the independent charity Crimestoppers on 0800 555111.”