Russian forces hit the city of Kharkiv in eastern Ukraine this morning with two S-300 missiles, Mayor Ihor Terekhov said on Telegram, as reported by the Kyiv Independent.
The attack was "directed towards infrastructure", stressed the mayor without providing further details on the targets hit.
There is still no news on the damage, nor on any injuries or victims.
The Kharkiv subway was closed after this morning's explosions and traffic "was completely restored", according to the Ukrainian media, citing the subway press service.
In addition, blackouts have occurred in some areas of the city.
Earlier, air-raid alerts were declared in six regions of eastern Ukraine.
A series of explosions was heard in the early hours of the morning in Kiev, without any air alarms being sounded: the website of the weekly Zerkalo Nedeli reports it.
"At the moment it is not known whether these were planned exercises or an enemy attack," adds the weekly.
Correspondents of the newspaper confirmed at least two explosions on the left bank of the Dnieper River, which crosses the city.
"The president's office has reacted to this incident by calling for calm, but no other details have yet been provided."
Explosions were also heard this morning in the Kiev region, as well as in the Ukrainian capital: the head of the regional military administration, Oleksiy Kuleba, underlined that a fire broke out in a critical infrastructure.
the website of the weekly Zerkalo Nedeli reports it.
"Kiev region. Around 6 in the morning (5:00 in Italy) explosions were heard. We have a fire in one of the critical infrastructures," said Kuleba without indicating the site of the explosions.
According to preliminary information, no injuries or victims were reported.
Russian forces again attacked the city of Zaporizhzhia in south-eastern Ukraine this morning, the mayor, Anatoly Kurtev, said, as reported by Rbc-Ukraine.
"In the morning, the enemy again attacked Zaporizhzhia. We are verifying information about the explosions heard by citizens," Kurtev wrote.
Local Telegram channels publish videos in which loud explosions are heard in these hours.
Also this morning, the Russians also attacked Kiev and its region, as well as the city of Kharkiv.
Russian forces struck twice with heavy artillery last night the Nikopol district of southern Ukraine's Dnipropetrovsk region, the head of the regional military administration, Valentyn Reznichenko, said on Telegram. reports Ukrinform.
"The district was hit twice with heavy artillery. Like the previous night, the Marhanets community came under enemy fire, which fired about 15 shells," Reznichenko wrote.
No injuries or casualties are reported.