A murder investigation has been launched following the disappearance of a man last month.
Detectives at Cumbria Police have confirmed its missing person inquiry for Paul Taylor had been escalated to a murder probe as of Wednesday 15 November.
Mr Taylor was last seen on Tuesday 17 October after leaving his home address in Annan, Dumfries and Galloway sometime after 9:45pm.
At the time, Police Scotland said officers were concerned for his welfare.
Cumbria Police said two 19-year-old men from the Carlisle area have been arrested on suspicion of murder and remain in police custody.
A 37-year-old man from Carlisle and a 17-year-old boy, from Appleby, also remain in custody after being arrested on suspicion of assisting an offender.
Detective Chief Superintendent Dave Pattinson said: "We have been working round the clock to try and find Paul since he was last seen on Tuesday 17 October.
"As the investigation has developed, and due to new information we have received, we are now treating the disappearance of Paul Taylor as a murder investigation.
"We are still requesting the assistance of the public to provide any information to us which may assist police, so we can understand the circumstances and events of what has happened.
"If you knew or spoke to Paul, in the weeks or months leading up to his disappearance or saw him or his car as he travelled from Annan to Carlisle on Tuesday 17 October, from 9:45pm onwards, we need to hear from you."
Mr Taylor's blue Corsa, with the registration PY18 DYO, was found abandoned in Langwathby on the morning of Thursday 19 October.
He added: "Don’t worry if you think the information is not important or may not be significant, it could be vital to help us establish what has happened to Paul and give his family the answers they deserve."
Police understand Mr Taylor’s car travelled towards Carlisle on the M6 Southbound shortly before midnight on 17 October.
It is believed the car then headed in the direction of the Kingmoor South area of Carlisle at around 11:35pm.
There have been potential sightings of the car in the Yewdale, Sandsfield Park and Brough Road areas early on 18 October.
Police continue to carry out inquiries to narrow down the route Mr Taylor took.
His car, a blue Vauxhall Corsa, was discovered in Langwathby at around 8:45am on Thursday 19 October.
The victim's family have been informed about the investigation and are being supported by family liaison officers.
Detectives are asking anyone with information to contact police by calling 101 or visiting www.cumbria.police.uk. Information can reported anonymously to Crimestoppers on 0800 555 111 or www.crimestoppers-uk.or.
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