FIREFIGHTERS are at the scene of a burning articulated lorry carrying wheat on Marlborough Road in Chiseldon.
Crews from Stratton and Swindon fire station are putting out the fire.
Traffic is queuing along the A346 near the junction with Butts Road.
A Wiltshire Police spokesman said: "We, along with DWFireRescue, are currently dealing with a lorry fire on the A346, Plough Hill, Chiseldon.
"One lane is currently blocked causing tailbacks in both directions, including onto the roundabout of J15 of the M4.
"Please find an alternative route if possible. Thanks."
UPDATE: The A346 is fully open and cleared as of 6pm.
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