Anyone who feels they know who it is should phone 101 or the Crimestoppers charity line anonymously on 0800 555 111
He says: "I'm going to leave you here, I'm going to take your wife (unintelligible). "You can ring the police in two minutes, we'll be round the corner." Police say they hope someone will recognise the distinctive accent.
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Police are appealing for information after a man died following a serious assault at one of London's busiest train stations.
Saturday morning's weather for the east of the region
Saturday morning's weather for the west of the region