A large sinkhole below a rail track near Forest Hill in south London has led to a number of train delays and cancellations between East Croydon and London Bridge.
Southern Rail warned that lines will remain closed until the end of the day, with a reduced service running out of London Bridge, following travel chaos on Monday evening.
And London Bridge station tweeted an apology to commuters for "severely disrupted" services today and this evening:
Network Rail posted a video on Twitter this afternoon showing work being carried out to fix the sinkhole.
"On Monday a large hole developed below the track in the Forest Hill area (between East Croydon and London Bridge)," Southern Rail said this morning.
"Assessments and plans were made to repair and fill the hole with additional ballast material that supports the track and work on this repair has continued overnight.
"We are not currently able to estimate when the line will reopen however we currently expect a complete closure until at least mid afternoon today."
The company tweeted a picture of the sinkhole:
Southern is running a reduced train service to and from London Bridge with train services using a diversionary route, meaning there will be no southern train services to or from Anerley, Penge West, Sydenham, Forest Hill, Honor Oak Park, Brockley or New Cross Gate stations.