M4 traffic news: Witness recounts moments before M4 crash

The crash, which took place around midday, led to long delays after two lanes were closed between Junctions 17 and 16. Eyewitnesses said it was caused by a car suddenly braking on the motorway. While the crash was cleared quickly, National Highways said a major spillage caused lanes two and three of the motorway to remain closed for hours.

“All I saw was a car brake heavily with nothing in front of it, and another car went into the back of it,” said one man who watched the crash take place. “I was driving the other way so I didn’t see any spillage, but that could have been why the car braked heavily,” he speculated. A spokesperson for Highways England at the time said: “We currently have specialist clean-up crews in attendance working to clear a spillage caused by the collision.

“At the moment there is no estimated time for all lanes to reopen, however traffic continues to pass the incident in lane one.” It is unclear whether the individuals involved in the crash sustained any major injuries. A spokesperson for Wiltshire Police said officers attended a crash on this stretch of the M4 at 11.30am, in which a vehicle crashed into the central reservation.

However, the force said this was a single-vehicle crash, and so it is unclear if it is a separate incident.