At 5 a.m. on July 26, a salvo of explosions interrupted the pre-dawn stillness in the Russian city of Stavropol when Ukrainian UAVs bombed the Signal Radio Plant, one of the nation’s most important defense electronics plants,

LONDON—Russia has launched a crash program to harden military airfields near the border with Ukraine in response to Kyiv’s successful strikes with one-way attack drones, the UK Defense Ministry has said. In its latest intelligence update published on July 29, UK defense officials posted satellite...