South West Trains say a problem at a level crossing between Barnes and Richmond means all lines will be blocked and services disrupted until around 6.30pm.
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Crossrail contractors have been hit with a fine of more than a million pounds over the death of a worker and other incidents.
Anh Nhu Nguyen, 52, claimed he lived in the North Kensington block and that his wife and son had died in the fire.
Roads will be closed in central London on Saturday 29 July and in London and Surrey on Sunday 30 July.