Chaotic scenes as Londoners try to escape the city before midnight lockdown. Police deployed to prevent non-essential journeys.

• The sudden announcement that London would be put on lockdown resulted in many Londoners trying to escape the city before midnight.
• Trains were fully booked shortly after the announcement was made.
• Footage emerged of a crowded St Pancras train station. Matt Hancock called it "totally irresponsible behavior."
• Police will be deployed at stations to prevent non-essential journeys being made, the Transport Secretary announced.

Following yesterday afternoon's announcement that $4, crowds of people made a last-minute attempt to escape the capital.

Train stations were mobbed as desperate Londoners tried to flee Tier 4 restrictions. Those trying to leave the city had a deadline of midnight before the tougher restrictions came in.

Trains out of London appeared to be fully booked, according to $4.

There were no trains available from the major terminals at Paddington, Kings Cross or Euston after 19:00 GMT, reports the$4.

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During Saturday's press conference, the UK's chief medical officer Professor Chris Whitty advised: "If you have packed a bag, unpack it."

This did not seem to deter many who were hoping to make it home in time for Christmas.

Footage taken at St Pancras station showed large crowds attempting to make it onto trains. Similar images of other train stations appeared on social media.

—Harriet Clugston (@HarrietClugston) $4

—Robert J F Barnes #DefundtheBBC #Boris (@RobertJFBarnes1) $4

—#McStrike ️‍ (@SocialistLew) $4

Reflecting on the viral footage, Health Secretary Matt Hancock told $4: "This was clearly totally irresponsible behavior, the chief medical officer was absolutely clear that people should unpack their bags if they had them packed."

On the trains, there was reportedly very little social distancing. "As expected, train is crammed," wrote journalist $4 "Announcement on tannoy says social distancing 'will not be possible' due to volume and to get off if you are not comfortable with that."

There are concerns that the new COVID-19 strain, which is up to 70% more transmissible, may be spread across the country by people traveling from Tier 4 areas to areas with lower infection rates. This is not permitted in the new rules.

Transport Secretary Grant Shapps $4 that extra police officers would be deployed at stations to prevent people from making non-essential journeys.

In a statement, he said: "It is incredibly important the people follow the guidance, stay at home and do not attempt to travel. Our focus must be stopping the spread of the virus, protecting lives and our NHS."

He continued: "If you are in Tier 4, the law means you must stay at home and you cannot stay overnight away from home. Across the rest of the country, you must stay local."