Network Rail and TfL have dismissed reports of a gas leak and said that overground and underground train services are running as normal.
Although four people have been taken unwell at London Bridge Station this morning, the Metropolitan Police has said there was nothing to link the cases at this stage.
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Negotiators from London Underground and three unions are meeting at the Euston offices of the concilliation service ACAS.
Clear periods and light winds tonight. Staying warm and muggy. Lows of 17°C.
It took police six days to launch a murder investigation after notorious British criminal John 'Goldfinger' Palmer was shot dead.