Three rapid response vehicles and five emergency ambulances were sent to the scene, where there were "multiple casualties", a spokeswoman for Welsh Ambulance Services NHS Trust said.
She added the ambulance service was called to the single vehicle collision at about 8.55am this morning.
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One story dominates Thursday's front pages with some newspapers printing emotive pleas to voters to keep the United Kingdom as one.
After a mild start temperatures should pick up, with the south of England seeing highs of 26C.
In Edinburgh tonight you can hear it and feel it. The buzz, the banter of the day and the thrilling sense something big is coming tomorrow.