9 people were left in a critical condition after a knife attack on a train in the UK. 

It is believed that a man on the train, which was moving from Peterborough to London on a fast-track line, pulled out knives and started attacking passengers once it was on the move.

UK Correspondent Gavin Grey told Andrew Dickens that the incident was not terror related. 

'Originally counterterrorism police were investigating this. We are now being told it is likely not to be terror related.'

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