Ukraine has stepped up its campaign of drone strikes inside Russia. Russian officials say at least 13 people, including a child, were killed on Monday in a drone attack on the city of Nizhnekamsk, where the TANECO oil refinery was also hit. Kiev says its wider long-range campaign is aimed at weakening the energy and logistics networks supporting Moscow’s war effort, and denies deliberately targeting civilians. TRT World’s Joel Flynn has been given rare access to a Ukrainian drone strike unit, and to one of the factories producing the weapons.