Source: Ukraine Emergencies Ministry / Facebook

By Ben Nimmo, DFRLab

On March 23, 2017 at 2:46am local time, a fire started at an arms depot in Balakliya, a town near Kharkiv and approximately 150 kilometers away from the front line where Ukraine is fighting Russian/separatist forces.

Source: Google Earth

The arms depot is the largest in the country, according to the BBC. It is just over 2.5km long at its widest, and half that width, covering an area of almost 350 hectares (850 acres).

Due to the sheer number of explosives stored at the depot, what started as a fire quickly turned into a chain of explosions:

It continued well into the morning and, as of noon local time, had not yet been brought under control, with EspresoTV reporting that there were 250 firefighters on the scene.

A large-scale evacuation was launched. By noon local time, almost 20,000 people appear to have been evacuated from the affected areas, and a fifty-kilometer danger zone had been declared around the burning depot.

Social media posts from the city center showed the presence of numerous emergency services.

Source: DSNS Ukraine / Google Maps. On the left, an image from social media shared on news sites showing a dozen ambulances standing in the city center. On the right, an image of the municipality building in Balakliya from Google Maps, confirming the location of the pictures at 49.451312, 36.840577

Source: @Bylbyleva / Twitter. The same municipality building can be seen in the left-hand photo; the apartment block to its right, marked in purple, is also visible to the left of the right-hand photo

A video posted by a Twitter user @ddya_sasha appears to confirm the scene set out by the pictures above:

Pictures from the aftermath of the initial explosions show damage to buildings in Balakliya. The images below come from a local group on the social network Vkontakte, and appear to show that the explosion at the depot set off munitions, some of which hit residential areas.

Source: Podslushano Bakaleya / VK

Source: Podslushano Bakaleya / VK

Source: Podslushano Bakaleya / VK

The large cloud of smoke coming from the depot was still visible in the sky during the morning, as seen in photographs from the State Emergency Service of Ukraine (DSNS Ukraine).

Source: DSNS Ukraine

Source: DSNS Ukraine

Although the investigation is ongoing, the Ukrainian authorities are treating it as sabotage:

Source: Anatoliy Matios / Facebook.

Translated excerpt from Facebook post by Anatoliy Matios, Deputy Prosecutor-General of Ukraine:

About Balakleya without panic (updated)

According to the preliminary results of the investigation of the investigative and prosecutorial group of higher prosecutors in the Kharkiv garrison and the investigative division of the SBU in Hankowski region (which is on the site of the event), the fire was a result of sabotage at started at 2:46am on several of the storage areas.

Ukrainian Defense Minister Stefan Poltorak said at a briefing that investigators were looking at various explanations, including the possibility that a drone had been used to start the fire.

According to the preliminary version, it was a diversion. Various ways of conducting the diversion are being considered, from the deployment of an unmanned aerial vehicle to a detonation.

The head of Ukraine’s SBU intelligence agency, Vasiliy Gritsak, appeared to confirm that this was one of the theories, saying, “If an aerial device can carry an explosive 35–40 kilometers, are there many ways of preventing it?”

So far, no details have been published which would allow for a closer analysis, with the investigation still ongoing. DFRLab will continue monitoring the evacuations and the investigation in the coming days.

By Ben Nimmo, DFRLab

Ben Nimmo is Senior Fellow for Information Defense at the Atlantic Council’s Digital Forensic Research Lab (DFRLab). Donara Barojan is a digital forensic research associate at the DFR Lab.