Four killed in helicopter, light plane mid-air collision in Britain

The entrance to historic Waddesdon Manor is cordoned off by police in Buckinghamshire, Britain, on Nov. 17, 2017. Several people were killed on Friday in a mid-air collision between a helicopter and a light aircraft in Britain. Wreckage from both aircraft were discovered near the estate grounds of historic Waddesdon Manor near Winchendon, Buckinghamshire. (Xinhua/Stephen Chung)