Urgent steps need to be taken to review the safety of rail lines following engineering works after a number of serious incidents, a report has said.

Issued today to Network Rail by the Rail Accident Investigation Branch (RAIB), the report said over the last four years there have been a number of incidents in which railway lines have been returned to service in an unsafe condition following work, causing potential danger to passengers.

These include an incident on June 18, 2015, when a passenger train struck a wooden sleeper on the line near Somerleyton. The previous day, the sleeper had fallen from a trailer which had been used to collect scrap material from the lineside.

In November 2015, the RAIB published a report on the accident, reinforcing the need for clarity on who is responsible for ensuring the safety of the line at the conclusion of engineering work.

The most recent incident occurred at Cradlehall near Inverness, on February 25 this year, when a train struck the end of a piece of rail about 130 metres long, which had been left on the up line at Cradlehall.

In the report, RAIB said: 'Over the last four years there have been a number of incidents in which railway lines have been returned to service in an unsafe condition following engineering works.

'In all such cases there is a real potential for serious harm to people on subsequent train services.

'In light of these incidents, and given the serious nature of the most recent incident, the RAIB advises Network Rail to take urgent steps to review the effectiveness of the steps it has already taken to address this risk, and to implement any additional measures that are required to ensure the safety of the line following engineering works.'

Responding to the report, Meliha Duymaz, Network Rail's route managing director for Anglia, said: 'We fully take on board the guidance set out in this report. We have emphasised to our maintenance teams the importance of thoroughly inspecting all completed work before any trains are allowed to run. The safety of our customers should never be put at risk.'