One person has died and almost 100 people have been injured after two trains collided in the Bedford area, with emergency services still at the scene and commuters battling long delays during the evening rush hour.

Of those injured, eleven people suffered “very serious” injuries and 22 were seriously injured, East of England Ambulance Service said, while a further 56 people had minor injuries and were treated at the scene or taken to hospital.

The two East Midlands railway services involved were the 4.40pm from Corby to St Pancras and the 3.50pm Nottingham to London St Pancras, the rail operator said.

Air ambulance helicopters were on the ground after the collision happened just south of the Elstow interchange between the A421 and the A6.

The Times reported that Bedford hospital staff had been told to expect as many as 50 injured people.

Members of the public were told to stay away from local hospital emergency departments on Friday night unless they were suffering from a genuine emergency.

A Rail, Maritime and Transport union spokesperson said it was deeply concerned by reports of a train collision and the “serious injuries sustained by onboard train staff and passengers”.

East Midlands railway services to and from London St Pancras were suspended for the rest of the night.

The prime minister, Keir Starmer, wrote on X: “Hugely concerning reports of a collision involving two passenger trains near Bedford.

“First and foremost, my thoughts are with the family of the person who has sadly lost their life, and with those who have been seriously injured.

“I am grateful to the emergency services for their swift response to this tragic incident.”

Video posted on social media showed a damaged purple Luton Airport Express train and passengers standing alongside the tracks.

Dr Peter Knapp, a passenger in the front carriage of one of the trains involved, told the Guardian: “There was no indication of any collision, no screeching of wheels, nor sirens or alarms. Suddenly there was an impact. I thought it was a bomb, I saw a lot of smoke and people on the floor, bloodied faces. A lot of people crying and screaming.

“I managed to open the doors and squeeze out. I was in quite a lot of shock, my glasses had fallen off.

“We were in the middle of nowhere in a field.”

Knapp added: “My two shins have got gouges in them from the chair in front.”

Knapp, 40, added: “I’ve got blood all over my trousers and my back hurts like hell but I’m alright.”

The rail accident investigation branch said a team of inspectors was at the scene to start gathering evidence.

Bedford and Kempston MP Mohammad Yasin said he was “very sorry” to hear of the incident.

One of the trains involved was the new East Midlands railway Aurora, which came into service last year.

The transport secretary, Heidi Alexander, said: “Deeply saddened to hear one person has died and a number of people injured in the awful train collision near Bedford.

“Our thoughts are with their loved ones and everyone affected. Emergency services remain on scene.”

She added: “Police have declared a major incident and Rail Accident Investigation Branch inspectors are on site. A full investigation will take place.”