A prolonged heatwave in Siberia is “undoubtedly alarming”, climate scientists have said. The freak temperatures have been linked to wildfires, a huge oil spill and a plague of tree-eating moths.

Most of the blazes are in a region that saw possibly the hottest-ever temperature above the Arctic Circle this month.

Much of Siberia this year has had unseasonably high temperatures, leading to sizable wildfires.