Russia has launched a missile attack on Ukraine's second largest city, Kharkiv, striking an industrial district, according to Mayor Ihor Terekhov.
"There is information about hitting an industrial zone in the city's Kholodnohirsky district," Mr Terekhov said on Telegram.
He provided no further information on casualties or damage.
Telegram channels reported explosions in the city.
It comes after Ukrainian officials said that Russia carried out new airstrikes and shelling in Ukraine overnight and early today, killing at least four people.
Kherson region governor Oleksandr Prokudin said a man aged 72 and an elderly woman had been killed in a Russian attack on the region, and three others were wounded, but gave no further details.
He said four others were hurt in a morning drone attack on the town of Beryslav, adding: "The occupiers deliberately attacked a crowded place, dropping explosives near the local bus station."
The general prosecutor's office said a man riding a bicycle had been killed in Russian shelling near the eastern town of Toretsk, and that a woman had been killed in an air strike at around noon in the eastern city of Avdiivka.
Odesa region governor Oleh Kiper said the Izmail district, home to Danube River ports that are used to export grain, had been targeted in a drone attack but gave no details of any damage to port or grain infrastructure.
He said 11 drones had been destroyed in attacks on the region and that an unspecified recreational facility in the small city of Vylkove had been hit.
A fire there was quickly extinguished, he added.
The governor of the neighboring Mykolaiv region said falling debris caused a fire in an unused building in the Snihurivka community, which was promptly extinguished, and a blast wave damaged nearby buildings.
He gave no further details.
Ukraine's air force said 18 out of 24 Russian drones were shot down, and that 17 cruise missiles were downed overnight over the Dnipropetrovs'k, Poltava and Khmelnytskyi regions.
The deputy governor of the Khmelnytskyi region said the blast wave had damaged the roofs and windows of several homes, and debris fell on the territory of an unspecified production facility and damaged a railway track.
It comes as Russia's defence ministry said its forces downed three Ukrainian drones over southwestern Crimea yesterday evening.
The ministry said air defence systems destroyed one drone at about 9.30pm Moscow time (7.30pm Irish time), an hour after it said its forces downed another two Ukrainian unmanned aerial vehicles in the same area.
Mikhail Razvozhayev, the Moscow-installed governor of Sevastopol, the largest city in Crimea and a major Black Sea port, said debris from the downed third drone fell over farmland and no damage was done.
He also said that if anyone saw smoke in the South Bay area, the Black Sea Fleet reported this was due to "standard aerosol camouflage." He said all was calm in the city and that despite the unpleasant smell from the camouflage, it was safe.
Earlier Russia's defence ministry said air defence systems also destroyed a Ukrainian drone over the Belgorod region. Russia did not comment on the latest attacks and has said it does not deliberately target civilians. Reuters was not able to immediately verify the reports.
Ukrainian retakes territory around Bakhmut
Elsewhere, Ukraine reported its troops had recaptured more territory on the eastern front and advanced in the south in its military counter-offensive against Russian forces.
Deputy Defence Minister Hanna Maliar said Kyiv's forces had retaken two square kilometres of land in the past week around the shattered eastern city of Bakhmut, which was captured by Russian troops in May after months of fighting.
Ukrainian forces also recaptured two villages on the southern flank of the city, Andriivka and Klishchiivka, Ms Maliar said.
Both cities lie on higher ground and their capture could set the stage to reasserting control over the pivotal city.
Ukraine's troops have liberated 51 square km near Bakhmut since the start of the counter-offensive, Ms Maliar said.
Further south in the Donetsk region, Ukrainian troops continued to hold back a Russian offensive towards the towns of Avdiivka and Maryinka, Ms Maliar said.
Ukrainian forces are trying to advance toward the Sea of Azov in a southern drive intended to split Russian forces retook 5.2 square km in the past week, said Ms Maliar.
Overall, Ukraine regained more than 260 square km in the south during the counteroffensive, she said.
During its three-month-old counter-offensive, Ukraine has reported slow, steady progress against entrenched Russian positions, retaking a string of villages and advancing on the flanks of Bakhmut, but taking no major settlements.
President Volodymyr Zelensky and other officials have dismissed Western critics who say the offensive is too slow and hampered by strategic errors.
"Today I would like to particularly commend the soldiers who, step by step, are returning to Ukraine what belongs to it, namely in the area of Bakhmut," Mr Zelensky said in his nightly video address to Ukraine.
The heavy fight for the Klishchiivka village, spread on higher grounds about 9km south of Bakhmut, has taken weeks and comes after Kyiv said on Friday it had gained control of a tiny nearby village of Andriivka.
The gains have been among the most significant in Ukraine's counter-offensive, which began in June and has struggled to break through entrenched Russian lines.
Oleksandr Syrskyi, commander of Ukraine's ground forces who is also in operational control of the counteroffensive, posted a video of Ukrainian forces displaying the blue and yellow national flag on ruined buildings with the sound of fighting in the background.
"Klishchiivka was cleared of the Russians," Mr Syrskyi, who has often visited the Bakhmut frontline to devise strategy and boost the troops' morale, said on the Telegram messaging app.
Reuters was not able to verify the reports and Russia has not confirmed the Ukrainian advances.
Yesterday, Russia's defence ministry said in its daily briefing that its forces kept up their attacks near Klishchiivka, which had a pre-war population of around 400.
Russia has been in control of Klishchiivka since January and still controls large swaths of Ukraine's land in the east and south.
