The Swindon to Highworth road has been closed following a collision.
The serious incident on Highworth Road, near to South Marston Industrial Estate and Stanton Park, is thought to have happened at around 5pm, 11 March.
Witnesses are reporting that the crash has blocked the road in both directions, with a large number of emergency service vehicles at the scene.
A dark grey car and navy blue car, both severely damaged, are said to be involved.
Another witness says that they saw a bicycle wheel under one of the vehicles, however, they are unsure if a cyclist was involved in the collision.