One person was killed early on Monday when Russian forces shelled the southern Ukrainian city of Kherson, while two others were killed in Russian shelling of border areas of the Kharkiv region in northeast Ukraine, officials said.
Both the city of Kherson and parts of the Kharkiv region are directly adjacent to the front line. The Ukrainian military has reported increased Russian attacks in the Kharkiv region in recent days.
"A difficult night for Kherson ... The Russian army continued to shell Kherson residents' homes in the central part of the city," governor Oleksandr Prokudin said on the Telegram messaging app.
Prokudin said the shelling had started around midnight and lasted for several hours.
Separately, the head of Ukraine's presidential office, Andriy Yermak, said on Telegram that two civilians had been killed and three others wounded during Russian shelling of border areas of Kharkiv region on Monday morning.
Reuters could not independently verify the details of the Ukrainian reports.
Ukraine recaptured Kherson city and parts of the Kherson region in November after months of Russian occupation, but Russian forces regularly shell the city and surrounding areas from across the Dnipro River.
This month a doctor was killed and five medical workers were wounded in Russian shelling of a Kherson hospital.
Russia denies deliberately targeting civilians or hospitals during its invasion of Ukraine, which is now in its 18th month and has resulted in the deaths of thousands of people, the uprooting of millions and the destruction of Ukrainian towns and cities.