Police are at the scene of a serious one-vehicle road traffic collision on the A1 south bound between Banbridge and Dromore.
The A1 is closed in both directions – south bound at the Banbridge Road junction at Dromore, and north bound at the Dromore Road junction, Banbridge.
The road is expected to be closed for some time as police continue with their enquiries.
A PSNI spokesperson said: “Drivers are advised, where possible, to seek an alternative route.
“We thank the public for their patience and co-operation.”
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