It has been 25 years since the start of the NATO air operation against the Federal Republic of Yugoslavia, which became known as Operation Allied Force.

On Sunday night, thousands of citizens gathered at the ruins of the former Headquarters of the Army in Belgrade – the building was severely damaged during air raids and the ruins were preserved as a memorial.

According to Euronews, some of the demonstrators held banners that read “When the army returns to Kosovo”, while others waved Russian flags, some with the symbol “Z”.

Earlier on Sunday, several Serbian cities held memorial services and tributes to the victims of the air strikes. In Belgrade, politicians, military, and foreign diplomats laid wreaths at a memorial for the child victims of the bombings.

A year after the start of the Kosovo War, marred by many serious war crimes, the official cause of Operation Allied Force was Serbia’s refusal to sign the Rambouillet Agreement – a plan that called for a complete Serbian withdrawal from Kosovo.

NATO decided to launch the operation without UN approval – as it was expected that China and Russia would veto any such UNSC decision anyway. This has since sparked debates about the legality of NATO’s actions.

The bombing began on March 24, 1999. The Serbian side claims that in addition to military and infrastructure targets, NATO bombed purely civilian places such as hospitals. The exact number of victims is not yet known. Various sources give very different estimates, from several hundred to several thousand civilians killed.

The operation officially ended on June 10, 1999, one day after the signing of the Kumanovo Agreement, which entailed the full withdrawal of Yugoslavia and Serbia from Kosovo and eventually led to the Republic’s full, if partially recognized, independence.

Also read: Serbia – Kosovo | Agreement on the European peace plan