Silver cylinder hovering above ground in Kent, Engalnd.

When on holiday in kent with family my 2 cousins and I were walking passed a field of blackcurrant bushes. We saw at the other side of a field a hovering silver cylinder slowly moving across the far end of the field. It seemed to be aware of our presence and changed direction, hovering above the bushes and heading towards us. We all ran back to our caravans and told our parents. When we returned it had gone. That same night while we were all asleep I was waken when my aunt and uncle burst into our home shaken and obviously terrifed. Something had shaken their caravan about and pulled off the door, whatever it was was chased away by their dog. the next day we saw the caravan, it was a complete mess smashed to pieces.
Date is approximate.  PD