DR Congo has declared Rwanda’s shooting of one of its fighter jets an “act of war”, amid mounting tensions.

Rwanda’s government said it took “defensive measures” against a plane that had violated its airspace – a claim denied by DR Congo.

This is a major escalation following months of conflict in eastern DR Congo, which has forced some 400,000 people to flee their homes.

DR Congo, the US and UN experts accuse Rwanda of backing the M23 rebel group.

Rwanda has denied this and blames the Congolese government for the conflict in the mineral-rich region.

In the 1990s, Rwanda twice sent troops into its much larger neighbour, sparking a huge conflict involving at least nine countries that led to the death of millions of people.