A third man has died following a two-vehicle crash on the M4.
The incident, involving a van and a lorry, took place on the westbound carriageway close to junction 17 at Chippenham shortly after 4.30am on Monday morning.
Two men travelling in the van were pronounced dead at the scene and two other men, also travelling in the van, were taken to Southmead Hospital in Bristol with serious injuries.
Wiltshire Police have announced that one of these men died from his injuries on Wednesday evening.
One of the three deceased has been formally identified as Martin Williams, 36 of Trecynon, Wales. Formal identification of the other two is likely to happen in the next few days.
The remaining victim remains in hospital in a critical condition.
A fifth male, who was driving the van, was taken to the Great Western Hospital in Swindon with minor injuries but was released the same morning.
A 37-year-old man from Aberdare was subsequently arrested on suspicion of causing death by dangerous driving. He has been released on police bail pending further enquiries.
The M4 westbound was closed for a total of nine-hours on Monday while the vehicles were recovered.
Anyone who witnessed the crash is asked to contact Wiltshire Police on 101 or Crimestoppers on 0800 555 111.
