Vladimir Putin's military command was preparing for a potential incursion into Russia's Kursk region months in advance, according to seized army documents.

A dozen other people were injured, some seriously, in the attack in the city of Sumy, which has come under increased bombardment since Ukraine’s offensive into Russia’s nearby Kursk region.

Over the past few months, Kyiv has grown in confidence and ambition as it has ramped up drone attacks inside Russia. It’s struck as far as 1,800km (1,118 miles) in the past, when a long-range radar was hit in the city of Orsk.