The main road between Calne and Lyneham has been closed by police.
Emergency services were called to reports of a road traffic collision at around 1pm this afternoon.
The crash is understood to be on the T-junction to Compton Bassett in Hilmarton.
Reports suggest police, fire and ambulance are all in attendance, alongside Wiltshire Air Ambulance.
A spokesperson for Wiltshire Police said: “At around 1.15pm we were called to a three-vehicle road traffic collision on the A3102 at Hilmarton.
“Officers and paramedics are currently at the scene and the road is blocked, so we would ask people to avoid the area.”