Vladimir Putin's army has suffered a devastating blow after a major ammunition depot was hit by Ukrainian missiles, according to an unverified video.

The strike produced a massive explosion, which sent a giant mushroom cloud of flames and smoke skywards.

Ukraine has stepped up its attacks on Russian supply lines and logistics in recent weeks, as it seeks to disrupt the momentum of Putin's army.

The strikes have targeted oil refineries, ammunition warehouses and air defence systems, particularly in Crimea.

Neither Russia nor Ukraine has commented on the recent attack in the occupied Donetsk region.

However, the commander of Ukraine's airforce confirmed that a Russian ammunition depot in Crimea had been hit on Monday in a separate attack.

His statement comes after videos of explosions near Sevastopol were posted to social media channels.

In a Telegram statement Mykola Oleshchuk wrote: "Once again, Ukrainian aircraft 'destroyed' by enemy propaganda continue to successfully perform combat missions, launch missile and bomb attacks on (Russian) occupied positions, and eliminate important military facilities in the enemy's deep rear."

Telegram channel Crimean Wind shared a photo reportedly taken by locals showing a tall column of smoke rising above Balaklava.

Explosions were also reported in the area of Cape Fiolent, according to Radio Free Europe.

Oleshchuk did not specify which ammunition depot was hit by Ukraine's military.

Ukrainian forces struck around 15 air defence systems in Russian-occupied Crimea over the past two months, according to Ukraine's Centre for Strategic Communications (Stratcom) in a report on June 17.