June 7 (UPI) — A Russian missile and drone attack in the Ukrainian city of Kharkiv early Saturday killed at least three people and injured more than 20 others, officials have confirmed.

Mayor Ihor Terekhov called the attacks in the country’s second-largest city “pure terror,” as Ukraine faced overnight bombardment for the third straight day.

At least four people died and more than 50 were injured during overnight missile and drone attacks early Friday morning that marked one of Russia’s largest aerial assaults of the year, involving almost 500 drones.

President Volodymyr Zelensky said the Friday attacks affected nearly the entire country.

Kharkiv faced “at least 40 explosions” during the overnight attacks, Terekhov said on his Telegram social media account.

“Kharkiv is currently experiencing the most powerful attack since the start of the full-scale war,” Terekhov wrote.

“The enemy is striking simultaneously with missiles, (drones) and guided aerial bombs. This is outright terror against peaceful Kharkiv.”

A 14-year-old girl and a boy under the age of two were among those injured in the latest Russian attacks carried out by over 50 drones and four guided aerial bombs, the Kharkiv regional prosecutor’s office.

Ukrainian officials said 18 apartment buildings and an additional 13 residential buildings were damaged in the attacks.

“The strikes achieved their objectives. All designated targets were destroyed,” Russia’s Defense Ministry wrote on Telegram.

The attacks came as the two countries were set to carry out a prisoner exchange that would see hundreds of soldiers on both sides repatriated, including the bodies of thousands of those killed in the conflict.

Russian officials on Saturday said Ukraine “unexpectedly postponed both the acceptance of bodies and the exchange of prisoners of war for an indefinite period,” following the latest round of attacks.