India, June 29 -- Ukraine kept up its heavy drone assault on Russia, setting fire to a major oil refinery in the south and killing at least two people, Russian authorities said on Sunday. Ukraine has markedly stepped up its long-range attacks on Russian military industries and energy facilities in recent months, aiming to cut Moscow's revenue for its invasion - now in its fifth year - and make Russians feel the consequences. The campaign has choked Russian fuel supplies and military deliveries. According to Western analysts, it has also slowed Moscow's efforts on the battlefield, heaping pressure on the Kremlin to come to the negotiating table. "Our 'long-range sanctions' reached two oil refineries in Russia," Ukrainian President Volodymy...