A "serious crash" has hospitalised three people with "suspected life-threatening injuries".
Officers were alerted to a crash on the A40 in Pembrokeshire, near the turning for Trecwn at 11:50pm on Friday, September 24.
Dyfed Powys Police, the Welsh Ambulance Service, Fire and Rescue, and the Coastguard helicopter all attended the scene.
A police spokesperson has confirmed three casualities were airlifted to hospital, and a further four were injured, however there is no information on whether they attended hospital.
Read more: All the latest news from Pembrokeshire
The three airlifted to hospital are said to have received suspected life-threatening injuries.
The road was closed overnight until just before 11am on Saturday, September 25.
Police are appealing for witnesses who may have noticed a white Skoda or red Chrysler travelling along the A40 before the time of the crash.
A spokesperson for Dyfed Powys Police said: "We are appealing for witnesses following a serious collision on the A40 in Pembrokeshire last night (Friday).
"Three people were airlifted to hospital with suspected life-threatening injuries, and a further four people were injured.
"The collision took place near the turning for Trecwn just before midnight (11:50pm).
"Ambulance and fire service also attended, with Coastguard helicopter assisting.
"The road was closed overnight as investigations took place.
"If you saw what happened, or noticed a white Skoda or red Chrysler travelling along that stretch of road in the time before the collision, please contact police by emailing 101@dyfed-powys.pnn.police.uk, call 101, or share what you know anonymously via Crimestoppers on 0800 555 111.
"You can also get in touch via our website using the following link."
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