Lithuania has been beleaguered by balloons drifting into its airspace from neighbouring Belarus. What are the military advantages of this seemingly whimsical mode of transportation? And how severe is the threat? Andrew Mueller explains.

Explainer 511: Why is Germany telling Syrians to return home?
07:12

Why has Israel invaded Lebanon?
33:29

Explainer 510: From Angola with love: are there Russian spies in southern Africa?
06:58