The death toll from a Russian strike on an ammunition depot in Ukraine's Kyiv region has risen to 38, with four people still missing, President Volodymyr Zelenskyy said Sunday.

The ⁠deadliest Russian strike in the Kyiv area this year took place late Friday as Moscow launched an intense campaign of attacks on the Ukrainian capital, which has continued over the weekend.

Friday's blast hit a military facility that held ⁠artillery shells, ⁠mines, drones and other ammunition.

Zelenskyy said on Telegram that first responders had managed to extinguish most of the fires. However, the scale of contamination in the area was significant and this work ⁠would continue for as long as necessary.

The president released video footage showing firefighting teams battling ​blazes and removing debris from destroyed buildings.

In its ​intensified attacks on the country, Russia over the last ⁠week ‌launched ‌nearly 2,000 strike drones, more ⁠than 1,600 aerial bombs, ‌and 31 missiles, including North Korean ​ballistic missiles, Zelenskyy said.

"We ⁠are seeking just ⁠responses to every Russian strike and crime. ⁠They ​will certainly come," he said.

Overnight Saturday, plumes of black smoke poured over the capital's western suburbs, while videos published by Ukraine's rescue services showed homes near the blast epicenter in flames, reported Agence France-Presse (AFP).

The attack was the second to hit a munitions depot near Kyiv in less than two months, with officials expressing anger that arms were still being stored so close to residential areas.

Both Russia and Ukraine have intensified long-range strikes on each other in recent months, pushing civilian casualties to their highest level since Moscow invaded in 2022.

"Those who allowed this to happen must be held accountable for their decisions ... ammunition cannot be stored near homes or other residential areas," President Zelenskyy said in a post on X.

The blast forced hundreds to evacuate and damaged multiple homes, including a care facility for elderly and disabled people, he added.

The mayor of the nearby town of Dmytrivka were also among the dead, Kyiv region Gov. Tymur Tkachenko said on Telegram.

Residents in the area told AFP the explosion was "terrifying."

"We thought we were being bombed. No one knew it was a detonation," said Yana Doneli, resident of a nearby town.

Zelenskyy blamed the incident on "horrific negligence," saying ammunition should not have been stored there.

'Criminal negligence'

Ukrainian prosecutors said they had opened an investigation into criminal negligence.

"On Aug. 28 at around 8:10 p.m. (1710 GMT), an unmanned aerial vehicle ... fell on or struck the grounds of an enterprise in the town of Myla," the office of Ukraine's prosecutor general said.

Myla is a small town on the outskirts of western Kyiv.

"A large-scale fire broke out on the enterprise's grounds and detonation began," prosecutors added.

The prosecutor's office said that its investigation would focus on "the legality of the ... storage of explosive objects and materials on the enterprise's grounds," as well as whether the owner, whom it did not name, had the "necessary permits and approvals."

Ukrainian Prime Minister Sergiy Koretsky expressed regret that a "lesson" had not been learned following a previous deadly strike on a munitions depot near Kyiv in July.

That investigation revealed serious failings on the part of a state-owned company, which did not comply with regulations regarding the proximity of residential buildings.

"In the fifth year of the full-scale invasion, making the same mistakes over and over is criminal negligence," he said on Telegram.

"Everyone responsible, without exception, must face severe punishment so that such situations never happen again," said Koretsky.