Queen Elizabeth II is set to unveil a new memorial to honor the 55,573 men of the RAF's Bomber Command who died in World War II.

The large number of civilian deaths in the campaign remains controversial, and is one reason there has been no memorial until now.

The German city of Dresden - where 25,000 civilians died in bombing raids - initially objected to the memorial. But the objections were eased by the placing an inscription commemorating all the lives lost in the bombings of 1939-45.

The service Thursday will be followed by a flypast of the Royal Air Force's last flying Lancaster Bomber.

The vintage plane will drop poppies over the park as a message of remembrance for those who died.