A serious crash has closed part of the A419.
Police have asked drivers to avoid the road in the wake of the incident, which happened earlier this morning.
In a statement on social media, Swindon Police said: "Closures are in place on the southbound carriageway between the Cricklade junction and Blunsdon."
"We will provide further updates when we can."
One motorist who drove past on the northbound side described seeing lots of police cars and a fire engine.
Wiltshire Air Ambulance has also been spotted at the scene.
No further details on the accident have been released at this stage and it is not yet known how many vehicles were involved.
The Adver has approached the police for an update.
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