Kyiv, 16 March 2024 (dpa/MIA) — At least 20 people were killed in Russian missile attacks on the southern Ukrainian city of Odessa - including rescue workers who tried to save others but were hit by a second missile, authorities said on Friday.

Ukrainian President Volodymyr Zelensky denounced the strikes, which also left 70 injured, as "heinous."

"Two missiles were fired, with the second hitting rescuers and medics who had arrived at the scene of the first strike," he said, adding that first responders were among the casualties.

The civil defence authority said 10 residential buildings were damaged by the explosions. Zelensky said on Friday night that the search of people possibly still trapped under the rubble continued.

The governor of the region, Oleh Kiper, declared Saturday a day of mourning.

Odessa and its port are a regular target of Russian missile and drone attacks in the war launched by Russia more than two years ago.

In other devastation in Ukraine from Russian attacks, at least two people were killed and three injured and taken to hospital from overnight drone attacks on the western Ukrainian region of Vinnytsia, the regional governor said on Friday.

Serhiy Borsov, in a Telegram post, said a residential building was hit.

Russia's military launched 27 combat drones from the south of the illegally annexed Crimea peninsula and from the north-east at targets in Ukraine, according to Ukrainian authorities.

Ukrainian air defence shot down all of the drones, including 15 that were destroyed on their approach to the capital Kiev.

However, as often happens, debris from the destroyed drones hits civilian objects.

Separately, the Russian border with Ukraine around the city of Belgorod came under fire again on Friday, the first day of Russia's much criticized elections, injuring two people, according to official reports.

Governor Vyacheslav Gladkov announced the attack on Telegram.

The Russian Defence Ministry said seven Ukrainian missiles were fired over Belgorod. This could not be initially independently verified.

People had to leave polling stations to seek shelter, the Russian state news agency Ria Novosti reported.

The ballot, which is intended to give Russian President Vladimir Putin his fifth term in office, is scheduled to run for three days until Sunday evening.

Putin described fresh attacks from the Ukrainian side on Belgorod as an attempt to disrupt the election.

"I am convinced that our people, the people of Russia, will respond to this with even greater solidarity," Putin said during a video link with representatives of the National Security Council.

The people would not allow themselves to be intimidated, Putin asserted.

Putin started a war against Russia's neighbour more than two years ago. However, paramilitary organizations often appear to be behind the attacks - forces that fight for Ukraine but consist mainly of Russian nationalists.

The organizations, with names like Russian Volunteer Corps, have reportedly already fought battles with the Russian army in the border region in recent days and have now announced further attacks on social media.