LONDON — Confusion is rippling through Britain after Prime Minister Boris Johnson ordered a three-week halt to all non-essential activity to fight the spread of the new coronavirus.

Streets were empty on Tuesday, but some subways were full. Hairdressers were closed, but construction sites were open.

The government has ordered most stores to close, banned gatherings of three or more people who don't live together and told everyone apart from essential workers to leave home only to buy food and medicines or to exercise.

But photos showed crowded trains on some London subway lines Tuesday morning amid confusion about who was still allowed to go to work.

On Tuesday, The Guardian reported that police fear enforcing Johnson's lockdown may be impossible, and that citizens confused by the order flooded departments' phone lines.

The Guardian says that according to internal police estimates, 10 percent of officers are either sick or self-isolating because of COVID-19 fears.

Britain has recorded 6,650 coronavirus cases and 335 deaths.