This is the moment a man, believed to be an anti-lockdown and anti-vaccine protester, suggested Prince Philip, Duke of Edinburgh, may have died due to taking the COVID-19 vaccine, addressing crowds outside Buckingham Palace in central London on Friday (April 9) as mourners had gathered to pay tribute to the late husband of the Queen.

Someone from the crowd shouted, "shut up you d***head" after the man said the COVID-19 vaccine was untested and potentially dangerous.

The man continued, saying "Prince Philip was forced ... to take a vaccine only three months ago - we need an autopsy of Prince Philip", which was met with boos and jeers from the crowd who had gathered to mourn him.

Police approached the man as he continued to suggest the vaccine may have been the cause of death, adding later, "let's hope [The Queen] doesn't die from any vaccine either".

He left after a police officer asked him, "you've made your point sir, could you please vacate?"

Buckingham Palace said in a statement that Prince Philip "passed away peacefully" at Windsor Castle on Friday morning. His cause of death has not yet been publicly stated.