Three hikers were injured, one of them seriously, by a tree that collapsed under the weight of snow in the Zittau Mountains in far-eastern Germany on Sunday. The group of four were hiking in a snow-covered forest area near Jonsdorf when a tree collapsed, a police spokesperson said. A 71-year-old man was trapped under the tree and had to be freed by the fire brigade. The man was seriously injured and taken to hospital by a rescue helicopter. A 70-year-old man and a 66-year-old woman were slightly injured. They were grazed by the tree and suffered cuts and lacerations from the branches, said the…