A social worker and street cleaner working for Southwark Council have died after contracting COVID-19.
Cllr Peter John, leader of the council, said he was "devastated" after hearing the tragic news.
He said: "Sadly the large number of tragic deaths that are expected nationally from COVID-19 means that all of us will know someone who has been touched by tragedy and loss by the time this is over.
"In Southwark we were devastated this week to learn that two colleagues have lost their lives to COVID-19.
"We are in touch with their families and are supporting staff at this difficult time.
"This is a tragic reminder that none of us is safe from this virus, and we must all do everything we can to prevent its spread by staying at home and away from other people."
People shared their condolences online, with Islington's leader Cllr Richard Watts describing council staff dealing with the crisis as "heroes".
Southwark has the highest number of confirmed COVID-19 cases in London at 368, and the fourth highest in the country.
The Department of Health and Social Care confirmed the death rate had more than doubled from 159 on Monday to 381 yesterday (March 30) – this represents the biggest day-on-day increase to date.
"As of 9am March 31, a total of 143,186 people have been tested, of which 25,150 tested positive.
"As of 5pm on March 30, of those hospitalised in the UK, 1,789 have sadly died," it said.
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