Video report by ITV News Correspondent Juliet Bremner
Crowds of passengers have descended on train stations in a bid to leave London ahead of new Tier 4 Covid restrictions.
It comes as households in London and the south-east England are to be banned from mixing over the festive period, with greater lockdown measures coming into force from midnight.
One passenger, Harriet Clugston, shared footage from St Pancras station in the capital before boarding a Leeds-bound train.
She tweeted: As expected, train is crammed. Announcement on tannoy says social distancing "will not be possible" due to volume and to get off if you are not comfortable with that.
She added: "Every person on this train including myself has made what is probably a very silly and irresponsible decision to travel albeit within the law. But that's what people were always going to do to be together at Christmas.
"My mother lives alone and there's no way I could not be with her at Christmas. Other will give similar reasons. What's at fault is the handling of this by Government - announce a midnight London lockdown at 4pm, obviously everyone will scramble to leave."
Another Twitter user shared a video showing similar scenes at the station.
Under the new tier 4 restrictions, a stay at home message will be put into law with exemptions for education, childcare and exercise.
All non-essential retail, indoor leisure, entertainment and beauty care (such as hairdressers and nail bars) will be forced to close.
Indoor hospitality, such as pubs, restaurants and cafes are already shut in these areas as they are in tier 3.
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