Commuters travelling on one of the country's busiest passenger rail networks face a second day of disruption to their journeys.
South West Trains (SWT) advised thousands of customers not to use its services into London on Wednesday after problems caused by a points failure and a passenger train derailment caused major problems on the line into Waterloo on Tuesday.
The incidents affected services into Britain's busiest railway station, which is undergoing huge improvement works that have temporarily closed more than half its platforms.
It came on the day it was announced that season ticket prices would rise by 3.6%, after the Retail Price Index (RPI) measure of inflation, which the Government uses to calculate the rise in regulated rail fares, rose by that amount in July, from 3.5% in June.
In a statement on its website on Tuesday, SWT said: "Trains are unable to use platforms one to 13 at London Waterloo and this reduction in available platforms means that many services will need to terminate before London Waterloo and many services will start away from London Waterloo.
"Most trains are experiencing severe delays and are subject to short notice alterations.
"Disruption to services is expected to persist until the end of service on August 16 2017.
"We now strongly advise customers not to travel on our network today or tomorrow."
None of the 23 passengers or two members of staff on board the train that partially derailed were injured, according to SWT and Network Rail.
Inquiries are under way to establish why the accident there and another at King's Cross happened, the British Transport Police and Network Rail said.
The 0513 from Royston in Hertfordshire hit buffers at platform nine at King's Cross at around 6.20am.
It was a "low speed" collision and the Rail Accident Investigation Branch has been informed, said operator Great Northern.