A woman was airlifted to hospital after being found motionless in the road.
Emergency services were called to near Merlin's Brook, in Clay Lane, Haverfordwest, on Monday, December 14.
The Welsh Ambulance Service confirmed that it received a call from a member of the public at 10.27am on Monday morning, reporting that a 60-year-old female had been found unconscious near Clay Lane.
A spokeswoman for the Welsh Ambulance Service confirmed that an emergency ambulance, a rapid response vehicle and a helicopter all attended the scene.
The woman was then taken by road to Withybush Hospital in Haverfordwest.
Dyfed-Powys Police confirmed it received a call from a member of the public at 10.40am, and that Clay Lane was subsequently closed to traffic.
Police are now appealing for any potential witnesses or anyone with any information to come forward.
A statement Dyfed-Powys Police said: "Police are making enquiries to establish what happened.
"Anyone with information that could help officers is asked to report it to Dyfed-Powys Police, either online at: bit.ly/DPPContactOnline, by emailing 101@dyfed-powys.pnn.police.uk, or by calling 101.
"If you are deaf, hard of hearing, or speech impaired text the non-emergency number on 07811 311 908.”
No further information has been released on the woman's condition - or how she came to be unconscious in the road.
Dyfed-Powys Police said it could not "currently provide further details".
