A 15-year-old was held on Thursday on suspicion of murder after a man was found with stab wounds to his stomach in the north of England.
Gwent Police said the victim was found outside a service station in the Tetney Vale area of Newport. Emergency services attended the scene and the 45-year-old man was found to have serious injuries and later died in hospital.
Initial inquiries show that the victim and the suspect know each other and the incident may have been linked to a carjacking last week.
The teenager was arrested on suspicion of murder. He has been taken to a police station to be questioned.
The Independent Police Complaints Commission will also investigate the police response to the incident. The IPCC said it is liaising with police and prosecutors to establish if there will be a formal criminal investigation.
Gwent Police also confirmed that a search warrant was executed on Thursday as part of the probe. Officers were seen leaving the property with a large plastic bag.