People have been trapped and injured after a multi-vehicle crash which involved a bus, emergency services say.
More than 70 homes lost power after the crash affected a power cable in Rhondda Cynon Taff.
South Wales Police said “there are casualties” following the collision at Trebanog Road in Porth at about 09:00 BST on Wednesday.
Firefighters are working to free people trapped in vehicles, and three people have been taken to hospital.
Two were taken to University Hospital of Wales, Cardiff, and one to Royal Glamorgan Hospital in Pontyclun.
Western Power is also at the scene dealing with the power cuts in the area, which appear to have been caused by the incident involving local power cables.
The road is expected to stay shut “for some time” and South Wales Police asked people to avoid the area.