Three explosions were heard, then electricity cut out on Tuesday in Ukraine's second city of Kharkiv, a Reuters witness reported.
"There are no lights in some parts of the city. Information about casualties is being specified," Kharkiv's mayor, Ihor Terekhov, said in his Telegram channel. He also reported a fourth attack.
Terekhov said an infrastructure facility was hit and said authorities were working to restore power as quickly as possible.
The report followed a rocket attack on Kharkiv Sept. 9 in which at least 10 people were wounded. Ukrainian officials said that attack was revenge for its forces' successes on the battlefield against Russia. [nL1N30G0ST]
((Reporting by Abdelaziz Boumzar; Editing by Chris Reese and Leslie Adler))
