Emergency services are in attendance at a serious crash near Llandovery.
One casualty has potentially life threatening injuries and fire crews are working on cutting them out of a vehicle.
A second casualty has been taken to hospital with serious injuries following the crash on the A40 between Manordeilo and Llandovery, before Llandovery bridge.
Update A40 Llandovery: Crews have used cutting equipment to free one casualty from a vehicle and are working to release a second
— Jennie Griffiths (@GriffithsJECtrl) November 16, 2017
Police say there are diversions in place at Llangadog roundabout and Llandovery roundabout.
A police spokesperson said: “Dyfed-Powys Police is still at the scene of a road traffic collision involving two vehicles on the A40 between Llandovery and Manordeilo, which happened shortly before 12pm today.
“The road is closed; diversions are in place at Llangadog and Llandovery.
“Fire and ambulance are also at the scene.
"Two people are injured - one person is being treated as having potentially life threatening injuries, another person has been taken to hospital with serious injuries.
“No further information is available at this time.”
Gridlock in Llangadog due to A40 diversion pic.twitter.com/qBjx8nLPox
— Richbroadway (@richbroadway) November 16, 2017
Mid and West Wales Fire and Rescue crews said they have used cutting equipment to free one casualty from a vehicle and are working to release a second.
The Welsh Ambulance Service was called to the scene at 11.50am.
A spokesperson for the Welsh Ambulance Service said: “Two crews in emergency ambulances and a paramedic in a rapid response vehicle are currently at the scene.”
* Road Closure * RTC A40 between Manordeilo and Llandovery (before Llandovery bridge). Diversions at Llangadog roundabout and Llandovery Rounabout. Avoid area please. @INRIXtraffic_W (97)
— HeddluDPPolice (@DyfedPowys) November 16, 2017
Motorists have been advised to avoid the area.
Gridlock has been reported in Llangadog due to the diversion.
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