A collision between two rail services near Bedford, which killed a train driver and left 100 people injured, was a "tragic, isolated incident", Network Rail has said.
The crash involved two East Midlands Railway (EMR) trains, with one smashing into the rear of the other on the same line just after 5pm on Friday.
Rail services around Bedford will be disrupted until 28 June, while a "complex recovery operation" continues to remove the damaged trains and carriages from the track, Network Rail has announced.
Engineers will then need to assess the damage and complete repairs, it said.
Rail passengers have been warned to expect disruption to services to and from Bedford for a week, and have been advised to only travel if it is "absolutely necessary".
There will be no services north of Luton on the busy commuter Thameslink line and no EMR services south of Bedford, Network Rail said.
It said there will be a limited rail replacement bus service between Luton and Bedford.
A 4.40pm rail service from Corby to London St Pancras smashed into the back of a 3.50pm Nottingham to St Pancras service on the same track at 5.15pm on Friday, derailing at least one carriage.
A major incident was declared, with 70 firefighters and 20 ambulances responding alongside police and medical helicopters to the collision just south of the Elstow interchange between the A421 and the A6.
Of the 100 victims, 11 people were very seriously injured, 32 were seriously hurt and 57 others sustained minor injuries, the East of England Ambulance Service (EEAS) said.
British Transport Police said more than 80 people were treated in hospital on Friday night, and 28 remained in hospital as of Saturday morning, with nine in a critical condition.
"While investigations are still at an early stage, current indications are that this was a tragic, isolated incident," said Ellie Burrows, Network Rail Eastern regional managing director.
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As part of recovery work, the overhead wires which provide power to electric trains will be removed and a temporary access road will be built for a crane to get close to the railway line.
Two 110-tonne Kirow cranes on the track will then lift the trains and carriages from the line, then a road crane will move them on to a trailer to be taken away by road, before engineers inspect the railway.
The work is expected to take days, with no EMR services to run between Bedford and London St Pancras over this period.
Trains that generally start and terminate at London St Pancras will do so at Bedford instead. There will be a reduced service on some other lines.
From Monday, north of London St Pancras towards Bedford, Thameslink will run a limited service as far as Luton only.
Sky News understands the accident investigation will take several months to complete.
The probe led by the Rail Accident Investigation Branch (RAIB) began at the scene of the crash on Saturday. It is possible the investigator may issue interim findings but there is no timeframe.
(c) Sky News 2026: Bedford train crash: Rail passengers to face disruption for a week after fatal collision

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