Commuters crammed onto the Central Line this morning hours after Boris Johnson announced a UK lockdown.
Pictures posted on social media showed people packed into busy carriages on London Underground.
Nurse Julia Harris, who commutes to work at Imperial College NHS Trust, said she had left earlier and changed her route to avoid crowds but still found the District Line to be busy.
Julia said the reduction in Transport for London services meant "you now have more people waiting and piling onto the tubes and trains".> "The issue is key workers aren't just health professionals - I think we under-estimated how many people are needed to keep things running."
As images appeared showing more crowding on the Tube network, Mayor of London Sadiq Khan tweeted:
Police chiefs warned of phone lines being inundated with calls on Monday night with questions about what movements are still permitted, while MPs also called for answers.