The A419 has been closed in both directions following a serious crash.
Emergency services are believed to have been called to the road traffic collision at around 6am this morning (18 September).
No details about the incident are known at this time, other than it occurred on the northbound carriageway near the junction with Wheatstone Road.
National Highways say the main road is closed between Junction 15 of the M4 and White Hard Roundabout.
A spokesperson for Wiltshire Police said: “We are currently dealing with a road traffic collision on the northbound carriageway of the A419.
“As a result, the road is closed northbound from the Dorcan junction at Wheatstone Road and southbound from the junction with the A420 and will remain closed for the foreseeable future.
“Please note there is no access to Swindon via Junction 15 of the M4, please use Junction 16.
“We ask that motorists please avoid this area if possible and find an alternative route. Thank you.”
UPDATE 8.45AM
A spokesperson for Wiltshire Police said: “We’ve re-opened one lane of the southbound carriageway, with traffic moving slowly.
“The northbound carriageway remains closed from junction 15 of the M4.
“Any witnesses to the incident are urged to contact us on 101 and quoting log number 67 of today’s date (18/09).”
