THE driver of one of the two trains involved in a crash in Salisbury is said to have sustained "life-changing" injuries.

British Transport Police said the South Western Railway driver remains in hospital in a stable condition.

The driver has not yet been named but his family have been informed. He is believed to being treated at the University Hospital Southampton.

Up to 13 passengers were taken to Salisbury District Hospital following the crash, which happened in the Fisherton Tunnel at 6.46pm on Sunday evening.

The 17.20 South Western Railway service from London Waterloo to Honiton crashed into the back of the 17.08 Great Western Railway service from Portsmouth Harbour to Bristol Temple Meads.

Both trains were travelling in the same direction and one train struck the side of the other, causing it to derail whilst in the tunnel.

The front few carriages remained upright while the back tipped on its side. There were 92 passengers on board the two trains, including a three-week-old baby.

Of the 13 people taken to Salisbury District Hospital, four were admitted, three of whom were discharged. One male passenger was kept in. Most of the injuries were soft tissue.

Meanwhile, an investigation has begun to determine how and why the accident occurred.

Detective Chief Inspector Paul Langley, of British Transport Police, said: “This will no doubt have been an incredibly frightening experience for all those involved and our thoughts are with them and their families today.

“Specialist officers and detectives remain on scene in Salisbury and we are working closely alongside the Rail Accident Investigation Branch (RAIB) and the Office of Rail and Road to establish exactly how these two trains came to collide.

“We are keeping an open mind but at this early stage there has been nothing to suggest the train struck an object or that there was any significant delay between the trains colliding and then one derailing.

The BTP said that while a number of people had been injured thankfully no one had died.

Around 30 of the ‘walking wounded’ were cared for at a casualty centre set up at St Mark’s Church in St Mark's Avenue, Salisbury.

The line through Salisbury is likely to be closed for the next few days as the accident investigators carry out their work and work begins to remove the trains from the tunnel.

Commuters have been asked to be patient while Network Rail, the two train operators and emergency services respond to the incident. There will be no trains running through Salisbury for the next few days.

There is a replacement coach service operating between Romsey and Salisbury. This is expected to last until Thursday, November 4.

South Western Railway said that services between Exeter and Basingstoke will be affected, while Great Western Railway services between Westbury and Portsmouth will also be impacted.