Two men have been killed and two seriously injured in a crash on the M5 motorway.
Police investigators believe the incident involved five vehicles and started when a Ford Mondeo and an MG Rover collided at 1.05am.
An HGV then stopped and was involved in a further collision with a black Mazda and a silver Mercedes.
The 24-year-old driver of the Mercedes died at the scene along with a 23-year-old passenger. Both men were from Gloucester.
Another passenger in the vehicle, a 23-year-old man from Gloucester, was taken to Queen Elizabeth Hospital in Birmingham in a critical condition.
The final passenger, another 23-year-old from Gloucester, remains in a critical condition in Southmead Hospital in Bristol.
A man who was a passenger in the Mazda and the driver of the Mondeo were taken to Gloucestershire Royal Hospital.
Both are believed to have suffered injuries that are not life-threatening.
The incident happened between junctions 8 and 9 southbound of the motorway, about half a mile south of the M50 junction.
A spokesman for Gloucestershire Police confirmed the motorway, which was closed for investigations to take place, has now reopened.
“Anyone who witnessed the collision or has any information but hasn’t yet spoken to police should call 101 and quote incident 17 of June 2,” the force spokesman added.
West Midlands Ambulance Service sent three ambulances, a paramedic area support officer and a MERIT trauma doctor to the scene at 1.15am.
South Western Ambulance Service also responded to the incident, sending additional ambulance resources including a doctor and hazardous area response team paramedics.
“Upon arrival, the emergency services found a car which had been involved in a serious collision with four men inside,” a spokeswoman for West Midlands Ambulance Service said.
“Sadly, nothing could be done to save two men and they were confirmed dead on scene. A third man was in a critical condition and received advanced trauma care by ambulance staff and the trauma doctor at the roadside.
“The man remains in a critical condition. A fourth man was given trauma care for back and leg injuries before being taken to Gloucestershire Royal Hospital.
“Four other patients from other vehicles involved in the collision were assessed and treated by South Western Ambulance Service colleagues.
“Despite the distressing nature of the incident, the two ambulance services together with police and fire colleagues worked as a team to provide excellent patient care on scene.”
