Services are not expected to return to normal on the Elizabeth line until around 9am on Friday after TSSA and Prospect union members walked off the job on Thursday amid a dispute over pay parity.
The industrial action finished at 6.30am, with no service between Abbey Wood and Paddington expected until around 7.30am. Services will run to and from Paddington and Liverpool Street National Rail stations before 7.30am.
Overhead wire problems are causing severe delays on the Overground between Stratford and Willesden Junction which is set to cause headaches for many Londoners.
The issue occured at Camden Road, Transport for London (TfL) said on Friday. There is a good service on all other Overground routes.
There are severe delays on the Piccadilly line between Acton Town and Cockfosters eastbound while TfL fixes a signal failure at Hammersmith. There is a good service on the rest of the line.
Tickets are been accepted on local buses.
Picket lines formed in Paddington and Romford on Thursday as Elizabeth Line workers demanded a pay increase more in line with their TfL colleagues.
London Mayor Sadiq Khan was urged to intervene on their behalf and “influence to encourage negotiations which can resolve this dispute”, in a letter by TSSA interim general secretary Frank Ward.
Unions say Elizabeth line staff employed by RfLi are paid up to £30,000 less than colleagues with equivalent roles elsewhere on the TfL network.
Bus drivers employed by Abellio in South and West London also striked on Thursday amid a pay dispute. Further bus driver strikes are planned for January 16, 19, 25 and 26.