A 23-mile stretch of the A470 in Powys has been closed after a gas tanker overturned in a field.
The incident happened between Llanbrynmair and Dolfach, near Machynlleth, at about 13:00 GMT.
Dyfed-Powys Police said the tanker was half full of gas, and the A470 had been closed between Caersws, near Newtown, and Mallwyd, near Machynlleth.
A recovery vehicle was sent to the scene, but it was not clear when the road would reopen.
Police said the lorry was on its side in the field, adding that it was the only vehicle involved.
It was unclear if there were any injuries to the driver.
Mid and West Wales Fire and Rescue Service sent crews from Machynlleth and Newtown to the scene.
Diversions were put in place.