Hundreds of people have been attending anti-racism demonstrations across the region this weekend despite warnings from ministers that mass gatherings are banned.
Worldwide protests over the killing of George Floyd in Minneapolis are heading into their second weekend amid public anger at police over his death.
Protests have taken place in Peterborough, Southend, Ipswich, Milton Keynes, Cambridge, Northampton and Norwich.
Professor John Edmunds, who attends meetings of the Scientific Advisory Group for Emergencies (Sage) supporting the government, said people attending should be “very careful”, wear face masks and observe social distancing rules.
It follows a warning from Health Secretary Matt Hancock at the government's daily coronavirus press conference that "we’re still facing a health crisis and coronavirus remains a real threat".
Home Secretary Priti Patel posted on Twitter, urging people not to gather in groups larger than six, "for the safety of all of us".