Two women have been stabbed in an East London park in separate attacks, less than 3 weeks apart.
Police are warning the public to be vigilant after the women were assaulted in Wapping Woods.
As Nick Thatcher reports, detectives are linking the incidents.
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The 24-year-old was unarmed and the incident is not being treated as terror-related.
Some platforms have been taken out of service with disruption expected to continue until the end of the day.
The Met Office has extended its weather warnings for snow and ice to cover vast swathes of the country, including London and the South East.