June 12 (Reuters) - Ukraine and Russia exchanged overnight drone strikes into early Friday, with Ukraine hitting oil refineries and a petrochemicals plant 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.
Ukraine's military said it struck Tatneft's oil refinery TANECO in the city of Nizhnekamsk in Tatarstan overnight, which it described as one of the biggest in Russia with an annual design capacity of over 16 million tons.
It also said in a statement on the Telegram messaging app that it struck the TAIF-NK refinery in Nizhnekamsk, adding that it confirmed fire at both refineries.
The Tatarstan regional head said earlier that industrial facilities in Tatarstan were targeted, while Nizhnekamsk will cancel public events on Friday amid the threat of drone attacks, the city's mayor said.
The country marks Russia Day on June 12 with a national holiday.
Ukraine's military said it also hit the Tolyattikauchuk plant in the city of Togliatti in the Samara region, which it said specialises in production of synthetic rubbers, which are used for making solid fuel for missiles.
The Samara regional governor said earlier that Togliatti, a city on the Volga River some 800 km (500 miles) southeast of Moscow, had also come under drone attack.
Separately, two people were killed and 10 were injured in a Ukrainian attack on Russia's border region of Bryansk, the acting regional governor said late on Thursday.
Russia downed 231 Ukrainian drones overnight, news agencies reported, citing Russia's defence ministry.
Both Russia and Ukraine deny deliberately attacking 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 and injuring another one, the chief executive of Ukraine's state railway Ukrzaliznytsia said on Friday.
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, Christopher Cushing, William Maclean)
