Police have launched an investigation after white paint was thrown over a war memorial and a statue of Sir Winston Churchill on Monday.

Britain’s last surviving Dambuster has criticised the “mindless vandalism” of white paint being thrown over the Bomber Command Memorial as it emerged it marks the fourth time in six years that the memorial in London’s Green Park had been sabotaged, the RAF Benevolent Fund said.

Former Dambuster Squadron Leader George “Johnny” Johnson, 97, said: “What a disgrace – such mindless vandalism.

“How disrespectful to the nearly 58,000 people who gave their lives so that these thugs have the freedom to carry out such acts. I hope they are caught soon, and suitably punished.”

Bomber Command veteran Air Commodore Charles Clarke, who was imprisoned in the Nazis’ Stalag Luft III, called the act “disgraceful and mindless”, adding it “did not achieve anything”.

CCTV footage from the memorial has been handed to police.

The Churchill statue in New Bond Street, central London, was also targeted with white paint, and images showed damage to the Graspan Royal Marines Memorial on The Mall.

Scotland Yard said officers were investigating reports of criminal damage to a number of statues in west London.

There were also reports of damage to the Canada Memorial in Green Park.

The RAF Benevolent Fund says repairs could run to thousands of pounds.

A statue of Franklin Roosevelt and Winston Churchill was defaced amond the statues which were defaced (PA)

Air Vice-Marshal David Murray, the charity’s chief executive, said: “This is the worst example of vandalism we have seen at the memorial, and it is utterly heartbreaking to see the memory of all those brave airmen disrespected in this way.

“This despicable act took just moments but will take considerable time and resources to put right.

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“But like the remarkable men who the memorial commemorates, we will not rest until we have finished the job.”

Former British Army officer Johnny Mercer, now a Conservative MP, also decried the vandalism.

He said: "The courage and aspiration these memorials commemorate is sorely lacking in some corners of Britain - and in fact her politics - at the moment."