The attacks came a day before a planned third round of direct peace talks between delegations from Moscow and Kyiv.
Ukraine President Volodymyr Zelensky’s announcement late on Monday that the negotiations would take place generated little hope they would deliver any progress on ending the three-year war.
That is despite the Trump administration’s efforts to push forward peace efforts, which have stalled as Russian President Vladimir Putin is reluctant to budge from his demands.
The previous two rounds were held in Istanbul, and Russian media reports said the Turkish city would also host the meeting this time.
Emergency services personnel work to extinguish a fire following a Russian attack in Odesa (Ukrainian Emergency Service via AP)
The talks in May and June led to a series of exchanges of prisoners of war and the bodies of fallen soldiers but produced no other agreements.
Russia is driving hard to break through at eastern and north-eastern points on the 620-mile front line. It is also firing upwards of 700 drones a night at Ukrainian cities.
From dusk on Monday evening, Russia struck the Ukrainian regions of Sumy in the north east, Odesa in the south and eastern Kramatorsk.
In Kramatorsk, a glide bomb hit an apartment building, starting a fire, according to the head of the city’s military administration, Oleksandr Honcharenko.
A boy born in 2015 was killed, local officials said, without giving his exact age. Five other people were reported wounded.
The Sumy region came under multiple waves of attacks, the regional military administration reported. A drone hit a fuel station in the town of Putyvl, wounding four people, including a five-year-old boy.
A second drone strike hit the same location less than two hours later, wounding seven more.
After dark, two powerful Russian glide bombs were dropped on Sumy city, wounding 13 people, including a six-year-old boy.
According to regional authorities, five apartment buildings, two private homes and a shopping mall were damaged in the attack. Acting mayor Artem Kobzar said the blasts shattered windows and destroyed balconies in residential buildings.
Also on Tuesday, Russia’s Defence Ministry claimed air defences downed 35 Ukrainian long-range drones over several regions overnight, including three over the Moscow region.