CCTV pictures have also been released of Samuel Guidera visiting a corner shop before he was stabbed.
After leaving the store, he walked towards the bus stop on Newlands Park, where he was attacked.
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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.