Out walking with a friend on the marshes next to the non navigable section of the River Lea on a clear sunny day (apart from a single cloud and a visible moon), facing roughly east towards the Leyton area when a something catches my eye against the blue. A small object at what looked to be at great altitude was travelling in a tight circle, and then joined by another following its trajectory. As the objects completed their circle and began to travel away they seemed to completely dematerialise from sight one after the other. They would then reappear, slightly further over. They repeated this pattern of slowly circling, vanishing then reappearing about four or five times before vanishing from sight entirely, leaving absolutely no trace.