ST. PETERSBURG, July 4 -- The fires at the oil terminal on the Gulf of Finland were visible from apartment windows across the port district before daylight on Saturday, the second time in a month that residents of St. Petersburg had woken to smoke rising from the same waterfront complex.

Ukrainian long-range drones struck the St. Petersburg Oil Terminal in the early hours of July 4, sending thick columns of black smoke above the harbor and setting multiple fuel storage tanks ablaze. Russian authorities in the Leningrad Oblast said air defense systems had intercepted 67 unmanned aerial vehicles overnight. Some reached their target. Photographs and video footage posted to monitoring channels showed the fires burning well past dawn.

The St...