LONDON (Reuters) – British Prime Minister Boris Johnson said on Friday it was “absurd and shameful” that a statue of Winston Churchill was at risk of attack by protesters, his strongest statement yet on a growing trend to challenge the legacies of past leaders.

Anti-racism protesters, who have staged demonstrations since the death of African American George Floyd after a Minneapolis police officer knelt on his neck for nearly nine minutes while detaining him on May 25, have put statues at the forefront of their challenge to Britain’s imperialist past.

The statue of Edward Colston, who made a fortune in the 17th century from the slave trade, was torn down in the city of Bristol on Sunday by demonstrators taking part in a worldwide wave of protests.

Before new protests on Friday and at the weekend, officials boarded up a statue opposite parliament of Churchill, Britain’s prime minister during World War Two, after demonstrators defaced it on Sunday.

“It is absurd and shameful that this national monument should today be at risk of attack by violent protesters,” Johnson wrote on Twitter.

“Yes, he sometimes expressed opinions that were and are unacceptable to us today, but he was a hero, and he fully deserves his memorial. We cannot now try to edit or censor our past. We cannot pretend to have a different history,” he wrote, calling on people to avoid the protests.

Johnson is an admirer and biographer of Churchill, and some of those close to him say he wants to emulate him.

Johnson has said he hears the “undeniable feeling of injustice” of those protesting but has also appealed to demonstrators to abide by social distancing rules to prevent a second wave of the novel coronavirus.

“Whatever progress this country has made in fighting racism – and it has been huge – we all recognise that there is much more work to do,” he said. “But it is clear that the protests have been sadly hijacked by extremists intent on violence.”