Russian attacks on two cities in Ukraine's southeast on Tuesday killed seven people and injured more than two dozen others, officials said, with Kyiv accusing Moscow of escalating strikes instead of agreeing to an Easter ceasefire.

A small FPV (first-person-view) Russian drone smashed into a bus approaching a bus stop in Nikopol's city center, Oleksandr Ganzha, the governor of the eastern Dnipropetrovsk region, said on the Telegram app.

Four people were killed, and at least 16 were injured, President Volodymyr Zelenskyy said.

"When such terror against people and lives occurs daily, blocking new sanctions against Russia, attempting to weaken existing ones, and trading with Russia all look bizarre," he said on X.

The images from the site he shared showed the burnt bus with smashed windows. Three bodies lay on the pavement nearby as rescuers were helping the injured.

In the southern city of Kherson, less than 5 kilometers (3.11 miles) from the frontline, a non-stop half-hour Russian attack on a residential area killed three elderly people and injured seven more, Regional Governor Oleksandr Prokudin said on Telegram.

Ukrainian officials and human rights organizations have accused Moscow's troops of deliberate and systemic FPV drone attacks on civilians, in particular in Kherson.

"In Kherson, civilians are effectively subjected to constant so-called 'safaris', with casualties every day," Zelenskyy said, commenting on the Tuesday attack.

Russia denies targeting civilians, but hundreds of thousands have been killed and injured in its strikes since Moscow launched the full-scale aggression against its neighbor in early 2022.