He is wanted in connection with the murder of Mark Noke, 64, who died of a stab wound at his home address in Warburton Road, Thornhill, in the early hours of Saturday, 25 February.
He is also wanted on recall to prison for breaching his licence conditions in connection with a knife possession offence he was convicted of last year.
Leighton has links to Southampton and Gosport.
Acting DCI Howard Broadribb is leading the investigation into Mark’s murder. He said:
“We want to speak to Leighton in connection with Mark’s death, and urge him to come forward.
“I would also like to remind anyone harbouring Leighton that they may be committing an offence and could be arrested themselves.
“If you see him, do not approach him – call 999 immediately.
“Officers have conducted a number of enquiries to find him and we are now turning to the public for their help. If you know where he is, please get in touch with us directly or anonymously through Crimestoppers.
“Extra officers continue to be on patrol in the Thornhill area in the wake of Mark’s death.”
Leighton is described as:
-5ft 11ins tall
-Slim build
-Blond, short hair
-Having a moustache and goatee, but could be clean shaven
-Brown eyes
Anyone with information about the case that could assist the enquiries should contact police on 101 or report online via their website quoting 44230077698 or Operation Hibiscus.
You can also send us information including CCTV footage online via the police website.
Alternatively, you can call Crimestoppers anonymously on 0800 555 111 or on their website.