Russia’s defence ministry says its forces have destroyed dozens of drones in several regions across the country, including Moscow.
The biggest attack happened in the southern Russian region of Krasnodar, where an oil refinery was targeted.
The attacks come as Russia holds a general election in which President Vladimir Putin is guaranteed to win.
In Ukraine, officials reported an overnight barrage of Russian drones and missiles on the port city of Odesa.
The Ukrainian governor of the north-eastern city of Kharkiv said 15 settlements had been shelled by Russia over the past 24 hours.
In Russia, authorities said 17 drones had been launched against an oil refinery and had been neutralised, but one sparked a fire as it fell.
No deaths were reported as a result of the fire, which has been extinguished.
One person is thought to have died of a heart attack during the strike. It is the sixth oil refinery attacked in Russia over the past week.
Meanwhile, Moscow Mayor Sergei Sobyanin wrote on Telegram that five drones were downed in different areas while flying towards the capital early on Sunday.
And two Moscow airports have imposed flight restrictions for security reasons, state media report.
Another area of Russia – the Belgorod region, near northern Ukraine – has also come under attack, according to its governor. He said a teenage girl had died when a shell hit a residential building.
Vyacheslav Gladkov said drones dropped explosive devices in the village of Oktyabrsky – damaging electricity and gas supply lines.
It is the second time Belgorod has been targeted this weekend.
On Saturday, at least two people were killed in a bombardment the authorities blamed on Ukraine. Shops and schools were closed afterwards as a safety precaution.
President Putin has accused Ukraine of trying to disrupt his bid for another six-year term. He is certain to win because he has no credible opponent. The vote is described as neither free nor fair by critics.
There were also reports on Sunday of Russian multiple air strikes on the Ukrainian port city of Odesa – days after a double missile attack killed at least 20 people and left dozens more wounded.
According to Ukraine’s southern defence forces, 13 Iranian-made Shahed drones were shot down.
While no injuries were reported, the attack caused fires at two agricultural sites and destroyed buildings. The fires have since been put out.
Another drone was shot down in the Mykolaiv region.
