A commuter train came within seconds of crashing into rubble after a wall collapsed at Liverpool Lime Street station.
The near-miss occurred during rush hour on Tuesday (25 February) between Lime Street and Edge Hill station at 5:45pm .
Up to 220 tonnes of debris were strewn across four lines outside the city's main hub following the wall collapse, leaving hundreds of passengers trapped on trains outside the station. Three trains were evacuated, but no injuries were reported as potential disaster was averted.
The Rail, Maritime and Transport (RMT) union said it understood "at least one train was seconds away from colliding with the collapse".
RMT general secretary Mike Cash praised the "magnificent response" of railway staff in averting what could have been a major disaster.
"Without guards to keep passengers calm and lead safe evacuations we would have had the potentially lethal prospect of passengers de-training themselves in cold, dark tunnels and stumbling towards tons of debris and damaged 25,000-volt overhead power lines."
Cash told Sky News the incident served as a warning that the driver-only trains planned by Arriva Rail North would be a "fundamental attack on safety for passengers and rail workers alike".
Services were severely disrupted by the incident as the station was cut off. Services began to return to normal on Thursday.
Services to Manchester, Warrington and Wigan were all severely disrupted by the collapse.
Network Rail chief operating officer Mark Killick said services in and out of the station, which handles over 15 million passengers a year, are expected to fully resume by 9 March.
"Firstly, we are making the location safe. This will allow us to start step two - safely accessing the tracks in the cutting more than 10 metres below to clear the debris.
"We will then move on to step three - repairing the damaged railway," he said.