Dyfed-Powys Police is investigating a serious assault in Station Road, Llanelli, last night (3 October).
Officers attended after a report of an assault outside the One Stop Shop at around 7.10pm.
The victim was taken to hospital with serious injuries.
A 20-year-old man has been arrested on suspicion of serious assault. He remains in police custody.
Anyone with information that could help officers with their investigation is asked to report it to Dyfed-Powys Police, either online at https://bit.ly/DPPContactOnline, by emailing firstname.lastname@example.org, or by calling 101.
If you are deaf, hard of hearing, or speech impaired text the non-emergency number on 07811 311 908. Alternatively, contact the independent charity Crimestoppers anonymously by calling 0800 555111, or visiting crimestoppers-uk.org. Quote reference: DPP/0536/02/10/2021/02/C.