Commuters have faced more disruption to trains through Clapham Junction.
Some services run by Southern have been cancelled while others are delayed.
This follows yesterday’s chaos when a power supply problem in the Clapham area led to some passengers being stuck on trains for up to five hours.
The Gatwick Express which had to be suspended on Thursday is operating normally.
Southern says tickets dated for Thursday can be used for travel today.
It advises travellers a number of trains will operate with a reduced number of carriages.
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