A driver has been arrested on suspicion of attempted murder after two separate collisions brought traffic to a complete standstill on the motorway network near Bristol.

The incident took place on Wednesday evening, 2 September, at the busy Almondsbury Interchange where the M5 northbound meets the M4 westbound. Emergency services were called to the scene just after 9pm following reports of an initial crash, which quickly escalated into a second incident on the carriageway.

According to Avon and Somerset Police, the sequence of events began when a car struck the central reservation. What followed turned a bad collision into a major police investigation across two major routes.

Officers report that after the initial impact, the driver stepped out of his vehicle. He was then involved in a second collision on the M4 carriageway involving two other passing vehicles.

Paramedics took both the driver and a passenger from the first car to hospital. While the passenger has since been discharged, the driver remains under police guard in hospital receiving treatment for injuries described as potentially life-changing, though not life-threatening.

Police confirmed that the motorist was arrested on suspicion of attempted murder, as well as on suspicion of driving while unfit through drink or drugs. As with any ongoing police investigation, these allegations remain subject to formal inquiries and the legal process.

The drivers of the other two vehicles caught up in the second collision were not arrested. Police confirmed they are treating them as witnesses, and both individuals are currently helping officers piece together precisely what occurred on the road.

The collisions caused immediate and severe disruption at one of the South West's most critical junctions. National Highways reported that traffic was unable to join the M4 westbound from either direction, leaving long queues of vehicles stuck on the motorway.

While emergency services worked at the scene, some witnesses reported seeing stranded motorists stepping out of their cars onto the road during the complete standstill. Both carriageways remained closed for well over an hour before police and highway crews were able to reopen them at around 10.30pm.

What we don't know yet is the full chain of events that led up to the first crash, or the specific circumstances that prompted the attempted murder arrest. Police have not released further details on what was said or done at the scene between the two impacts, and that remains the central focus of their investigation.

Avon and Somerset Police are urging anyone who saw either collision or the moments immediately afterwards to come forward. If you were travelling through the Almondsbury Interchange around that time, or if you have dashcam footage, you can contact officers on 101 quoting reference 5226252893.

I'll be following this investigation closely as officers conclude their initial interviews — check back here for updates as more information emerges.