Russia bombarded six regions of Ukraine in one of its largest aerial attacks of the three-year war, Ukrainian officials said Friday.

The nighttime assault lasted for hours and killed three emergency responders in the capital Kyiv, according to authorities.

"In total, there were over 400 drone strikes and more than 40 missiles, including ballistic missiles," said President Volodymyr Zelenskyy, speaking at the International Summit of Cities and Regions in Kyiv.

"The Russians even burned down another warehouse with humanitarian aid," he added.

Ukrainian forces said they shot down about 30 of the cruise missiles and up to 200 of the drones.

The war has continued unabated even as a U.S.-led diplomatic push for a settlement has brought two rounds of direct peace talks between delegations from Russia and Ukraine.

The negotiations delivered no significant breakthroughs, however, and the sides remain far apart on their terms for an end to the fighting.

Ukrainian cities have come under regular bombardment since Russia invaded its neighbor in February 2022.

The attacks have killed more than 12-thousand civilians, according to the United Nations.