Several feared dead after plane and helicopter in mid-air collision

Several people are feared dead following a mid-air collision involving an aircraft and a helicopter in Buckinghamshire.Thames Valley Police, attending the scene near Waddesdon, say "preservation of life" is a priority.The crash is understood to have happened in Upper Winchendon, close to Waddesdon Manor, though a spokeswoman for the estate said it had not happened on its grounds.