June 12 (Reuters) - Ukraine and Russia exchanged overnight drone strikes into early Friday, with Ukraine targeting a major oil processing and petrochemical region while Russia attacked railway stations and electrical substations.
Ukraine's strikes hit an apartment block in Russia's central Tatarstan injuring three, and Russia's attack in Ukraine's Sumy region killed a railway worker, officials said.
The strikes follow large air attacks by Russia on Ukraine in recent weeks, while Kyiv has intensified long-range drone strikes on Russian oil facilities, leading to shortages of fuel in Crimea and elsewhere.
Industrial facilities in Tatarstan were targeted, regional head Rustam Minnikhanov said on the Telegram messaging app. Regional city Nizhnekamsk will cancel public events on Friday amid the threat of drone attacks, its mayor, Radmir Belyayev, also said.
The country marks Russia Day on June 12 with a national holiday.
Belyayev did not mention damage caused by drones. Several major industrial facilities are located in the area, including a petrochemical plant of Sibur's Nizhnekamskneftekhim and Tatneft's oil refinery TANECO.
Togliatti, a city on the Volga River some 800 km (500 miles) southeast of Moscow and home to Russia's biggest automaker Avtovaz, has also come under drone attack, the regional governor said.
Separately, two people were killed and another 10 injured in a Ukraine attack on Russia's border region of Bryansk, Acting Regional Governor Yegor Kovalchuk said late on Thursday.
Russia downed 231 Ukrainian drones overnight, news agencies reported, citing Russia's defence ministry.
Both Russia and Ukraine deny deliberately targeting civilians.
RAILWAY INFRASTRUCTURE IN UKRAINE UNDER ATTACK
Russian drones attacked railway stations, electrical signalling posts and substations in Ukraine's northern Sumy region, killing a railway worker, the chief executive of Ukraine's state railway Ukrzaliznytsia said on Friday.
CEO Oleksandr Pertsovskyi also said another railway worker was injured. The attack followed an overnight one on Thursday when a railway worker was killed and four injured in an attack on the town of Konotop, also in the Sumy region.
Ukraine's air force said Russia had launched 117 drones since 6 p.m. local time (1500 GMT) on Thursday, with air defence units downing or neutralising 102 of them.
Three people were injured in a drone attack in the southern city of Mykolaiv overnight, local authorities said on Telegram, reporting damage to 14 private buildings. Another drone attack early on Friday injured a man, they said.
Reuters could not independently confirm the reports.
(Reporting by Jekaterina Golubkova in Tokyo and Anna Pruchnicka in Gdansk; Editing by Chris Reese and Christopher Cushing)
