The Metropolitan line is suffering severe delays this morning following reports of a trespasser on the track at Northwick Park.
The line was earlier suspended between Harrow-on-the-Hill and Wembley Park, but has now reopened with major delays, with tickets being accepted on reasonable alternate routes.
There are also delays on the Elizabeth line due to a earlier signal system failure at Ealing Broadway.
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Live updates
DLR update
There are minor delays on the DLR between Canary Wharf and Lewisham due to a track fault at Lewisham.
There is a good service on other DLR routes.
Trespassers between Reading and Newbury
Trespassers on the railway between Reading and Newbury are causing severe delays.
The incident has now been cleared and the line has reopened, but there will still be cancellations and delays throughout the morning as service recovers.
This is affecting Great Western routes between Penzance, Newquay, Plymouth, Paignton, Exeter St Davids, Westbury, Newbury and London Paddington, between Bedwyn and Newbury, and also between Newbury and Reading.
Tube and Overground update
Through rush hour, there is a good service on the vast majority of the Tube and Overground network, with just minor delays on the Metropolitan line.
Reduced service between London Victoria and Orpington all day
Safety checks carried out overnight have identified a section of defective track on the line from London Victoria to Beckenham Junction via Herne Hill.
As such, a speed restriction has been put in place between Brixton and Beckenham Junction, meaning a reduced service will run between London Victoria and Orpington via Herne Hill until the end of the day.
Some work has been already been carried out but further work to repair the track will take place tonight
Elizabeth line update
There is a good service again on the Elizabeth line.
Tube update
The Metropolitan line has now reopened between Harrow-on-the-Hill and Wembley Park, albeit with severe delays.
There remain minor delays on the Elizabeth line, while the rest of the network is running with a good service.
Disruption between Liverpool Street and Tottenham Hale
Overrunning engineering works between London Liverpool Street and Hackney Downs are causing some delays this morning.
All lines have now reopened, but trains running between Liverpool Street and Tottenham Hale may still be cancelled or revised whilst service recovers.
This will affect Greater Anglia services between London Liverpool Street and Hertford East, Bishops Stortford, Cambridge, Cambridge North and Ely, as well as Stansted Express services between Liverpool Street and Stansted Airport.
Elizabeth line update
There are minor delays on the Elizabeth line this morning between Paddington and Heathrow Terminals / Reading due to an earlier signal system failure at Ealing Broadway.
There is a good service on the rest of the line.
Metropolitan line part suspended
There is currently no service between Harrow-on-the-Hill and Wembley Park on the Metropolitan line, and severe delays on the rest of the line, due to a trespasser on the tracks.
Tickets are being accepted on London Buses, London Northwestern Railway and London Overground via any reasonable route.
Good morning
Welcome to our live travel coverage - we will be keeping you updated with the latest travel news around London this morning.