World leaders have paid tribute to those who took part in the D-Day landings. The Second World War offensive, the biggest military operation in world history, began the liberation of mainland Europe from Nazi domination. However, as Richard Bestic reports from Portsmouth - the home of the British Royal Navy - the prize came at a huge cost in lives.

Looking back to the biggest military offensive in history, world leaders paid tribute to the bravery of those 150, 000 young men who began the Liberation of Europe with the D-Day landings. Britain's Monarch Queen Elizabeth speaking personally for the wartime generation.

On the 6th of June 1944, allied forces stormed the Normandy coast to take back occupied France. An unprecedented seaborne invasion paved the way for the end of Hitler's Nazi regime. Four and half thousand brave young men killed in a single day. Ninety-three year-old Frank Devita, a crew member on a Higgins landing craft, remembers a bloodbath.

FRANK DEVITA WORLD WAR II VETERAN "I cry every time I come here. I cry. These young kids - 18, 19,20 years old."

Tributes for the breath-taking bravery of a generation of real heroes came from above as well as below. Among the audience, watching the great and good up on stage, those who'd survived. Who'd played a part in changing world history. Scientists studying to this day the raw plans which triggered the beginning of the war's end.

RICHARD BESTIC PORTSMOUTH, ENGLAND "For all the emotion of this remarkable occasion here in the home of Britain's Royal Navy and in the company of that now dwindling band of brothers who witnessed it, this is in reality just a curtain raiser for the main event in Normandy, when veterans from all over Europe will join political leaders and remember the searing poignancy of D-day itself. RB CGTN Portsmouth England."