Explosions at two large Ukrainian military depots this year have caused losses of ammunition so high that they represent the biggest blow to Ukraine's combat capability since the start of the conflict with Russia-backed separatists in 2014, a senior security official said on September 28 in Kyiv.

Massive blasts followed by a blaze at a military depot near Kalynivka in the Vinnytsya region, 270 kilometers west of Kyiv, forced the evacuation of 30,000 people on September 27. Another depot in the eastern city of Kharkiv was destroyed in March. That blast was blamed on sabotage.



Electricity and gas supplies were cut off in the Vinnytsya area, and trains were severely delayed across the country.

In Kalynivka, firefighters on September 28 were still unable to put out the blaze because there were still periodic explosions at the site, said Mykola Chechotkin, chief of the State Service for Emergency Situations.

"The country has suffered the biggest blow to our fighting capacity since the start of the war," the secretary of the Security and Defense Council, Oleksandr Turchynov, told journalists.

WATCH: A huge ammunition depot in Balaklia, near Kharkiv in the northeast of the country, exploded on March 23. Drone footage showed the extent of the disaster.

However, the country's chief military prosecutor ruled out the possibility that the blast had been caused by foreign saboteurs.



According to local media reports, about 188,000 tons of munitions were kept at the depot, including shells for Grad multiple-rocket launchers.

Chief military prosecutor Anatoliy Matios on September 28 rejected earlier statements from authorities suggesting that foreign saboteurs may have set the depot on fire.

Matios said investigators were looking into possible negligence, abuse of power, or sabotage by those who were authorized to handle the ammunition.

He added that the investigation found that the fire alarm at the depot wasn't functioning and that its security team was understaffed.

"Neither the investigators, nor the Security Service, nor any law enforcement agencies found any groups of saboteurs in the Vinnytsya region that people are talking about on Facebook," Matios said, an apparent reference to comments made by several senior Ukrainian officials on social media on September 27 blaming Russian saboteurs for the fire.

In the aftermath of the blast, authorities said they launched checks at military bases across Ukraine and discovered serious violations.

Investigators found a colonel and a lieutenant colonel in charge of security at a military depot holding Soviet-era ballistic missiles who were "completely drunk," Matios said.

"I think such cases are not unique," he said, quoted by the Interfax news agency.

With reporting by AP, Reuters, and Interfax