Network Rail has apologised after passengers on their way to and from Gatwick Airport faced delays to their journeys.
The rail network operator blamed sinkholes for the disruption, which were discovered during planned engineering works.
In a statement, Network Rail said: "We're sorry for the disruption passengers faced today on the line between London Bridge and Gatwick Airport.
"During our planned engineering work on the lines outside Purley, engineers discovered that a number of sinkholes had appeared on a bridge south of the station.
"For the safety of passengers, we had to close all lines between Purley and East Croydon, impacting journeys towards Gatwick Airport.
"Over the course of the afternoon our engineers have carried out thorough inspections on the bridge and have worked to plug the sinkholes, allowing trains to safely run again.
"Though trains are now running we do expect there to be disruption into the night so we're urging passengers to check before travelling.
"We will be accepting today's [Sunday's] tickets on tomorrow's [Monday's] services due to the disruption today.
"We understand this made customers' journeys between London and Gatwick Airport very challenging today, and we apologise for the impact this has had."
(c) Sky News 2026: Network Rail apologises after sinkholes cause delays for Gatwick passengers
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