A man wanted over the disappearance of an Aucklander appears to be taunting police on social media.
Counties Manukau police have launched an investigation into the disappearance of Lance John Murphy.
Mr Murphy, 56, is from Waiuku and was last seen at the BP service station in Warkworth at about 6.35pm on 21 November.
Police said his car - a 2010 Mazda 6, registration HMZ40 -was found in Warkworth five days later.
Officers and his family have grave concerns for his safety.
Police are looking for Steve Gunbie, 37, saying he had access to firearms and should not be approached.
There is an arrest warrant out for Mr Gunbie for failing to appear on a disqualified for driving charge.
Detective Inspector Uraia Vakaruru said a search led them to Mr Murphy's car, at property owned by Mr Gunbie.
But police will not elaborate on how much blood was found in the car of the missing man.
Mr Vakaruru said blood identified as Mr Murphy's was found in the car, but would only say they had grave fears for his safety.
Counties Manukau Police have posted an appeal for information about the case on their Facebook page, asking for anyone who knows of Mr Gunbie's whereabouts to get in touch with them.
A person claiming to be the wanted man has made at least two posts on that Facebook page - the last saying Mr Gunbie was driving around without a licence:
Police said any information as to the whereabouts of Mr Gunbie or sightings of Mr Murphy and his Mazda 6 Vehicle can be provided to the Operation COSMOS investigation team at 0508 422 443 or you can call Crimestoppers anonymously on 0800 555 111.