Covid-19 measures for the capital. Extra police officers are to be deployed to enforce travel rules at London's stations, with the public being urged to adhere to Government guidance.The packed out trains came after Boris Johnson placed millions of people living in Tier 3 parts of London, the South-east and East of England in a new Tier 4.The changes, which came into force at midnight on Saturday, mean households mixing over Christmas is banned, travel into or out of Tier 4 areas is only permitted for very limited reasons and overnight stays away from home are largely prohibited.Appearing on the BBC's The Andrew Marr Show on Sunday, Mr Hancock said: "I think those scenes were totally irresponsible."We have all got a responsibility."We in.