The hunt for 24-year-old Kyle Vaughan from Newbridge has now become a murder investigation.
A 27-year-old man from the Blackwood area was arrested on suspicion of murder on Thursday January 10.
He remains in police custody at this time assisting detectives with their inquiries.
Kyle remains missing, with the last confirmed sightings on the evening of Sunday December 30 in the Abercarn and Risca areas.
On the same night at approximately 11.45pm, officers found Kyle's car - a silver Peugot 306 - on A467 between Risca and Crosskeys. It is believed the car had been involved in a collision and officers are appealing for anyone who saw the vehicle to come forward.
Kyle is described as 5ft 8ins, of slim build, with short dark hair, and brown eyes. He wears a gold neck chain with a cross and has a distinctive tattoo of a pair of flaming dice on his inner left forearm.
Senior investigating officer Detective Superintendent Peter Jones said: "At this time Kyle has been missing for 12 days, which is completely out of character for him.
"Specialist search officers have been deployed and have conducted detailed searches of several areas over the last week. These searches have included the use of a search dog.
"Family liaison officers are providing Kyle's family with support at this very difficult and upsetting time.
"I'm urging anyone who has any information about Kyle's disappearance, no matter how unimportant it may seem, to contact Gwent Police on 101.
"Information can also be passed on with complete anonymity via Crimestoppers on 0800 555111."
A 27-year-old man from the Blackwood area was arrested on suspicion of murder on Thursday January 10.
He remains in police custody at this time assisting detectives with their inquiries.
Kyle remains missing, with the last confirmed sightings on the evening of Sunday December 30 in the Abercarn and Risca areas.
On the same night at approximately 11.45pm, officers found Kyle's car - a silver Peugot 306 - on A467 between Risca and Crosskeys. It is believed the car had been involved in a collision and officers are appealing for anyone who saw the vehicle to come forward.
Kyle is described as 5ft 8ins, of slim build, with short dark hair, and brown eyes. He wears a gold neck chain with a cross and has a distinctive tattoo of a pair of flaming dice on his inner left forearm.
Senior investigating officer Detective Superintendent Peter Jones said: "At this time Kyle has been missing for 12 days, which is completely out of character for him.
"Specialist search officers have been deployed and have conducted detailed searches of several areas over the last week. These searches have included the use of a search dog.
"Family liaison officers are providing Kyle's family with support at this very difficult and upsetting time.
"I'm urging anyone who has any information about Kyle's disappearance, no matter how unimportant it may seem, to contact Gwent Police on 101.
"Information can also be passed on with complete anonymity via Crimestoppers on 0800 555111."
