With Southwark having more COVID-19 cases than any other borough, the council leader Peter John has urged residents to heed advice to stay at home. Playgrounds will now be locked to highlight the risks of unnecessary social contact.
In an email sent on Sunday morning to the council's mailing list, Cllr John made a direct appeal to local people: "Every one of our residents is important to us. You are important to us.
"But many residents are ignoring national advice and going out when we should all be staying at home as much as we can.
"This puts us all at risk of COVID-19, especially people who are over 70 or who suffer from ill-health.
"We know this is a worrying time, especially if you live alone, and we really want to help.
"There are lots of volunteers in our communities who want to help too. So instead of going out, please think about other ways to do things."
On Sunday afternoon Cllr John announced that all playgrounds in council-run parks would be locked on Sunday evening until further notice.
Picnics and barbecues will also be banned, according to deputy leader Rebecca Lury whose portfolio includes parks.
The borough's libraries and leisure centres have already closed.
Figures published on Saturday show 134 Southwark residents have tested positive from COVID-19, an increase of 24 on the previous day.
Given that testing is restricted to those already in hospital, this figure does not reflect the true spread of the virus in the borough.
Mayor of London Sadiq Khan has also spoken firmly and directly to Londoners urging them to avoid non-essential travel and to only leave their homes to obtain food or for exercise.
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