Kiyv: Ukrainian President Volodymyr Zelenskiy on Saturday said that Russia bombed a blood transfusion centre in the Kharkiv region of north-east Ukraine and slammed the deadly strike as “a war crime”.

In another strike, Russia hit a key factory owned by Motor Sich, which manufactures plane and helicopter engines and other components.

“Russia's guided air bomb against a blood transfusion center in Ukraine. This evening, Kupiansk community in Kharkiv region. Dead and wounded are reported. My condolences! Our rescuers are extinguishing the fire,” Zelenskiy tweeted on August 6.

These attacks come after Moscow's withdrawal from an agreement last month, which had allowed Ukraine to continue exporting grain despite the ongoing conflict.

A “guided air bomb” hit the centre in Kupiansk, a city a few dozen kilometres from the Russian border, he said.

“This war crime alone says everything about Russian aggression. Beasts that destroy everything that simply allows to live. Defeating terrorists is a matter of honor for everyone who values life,” Zelenskiy added.

The bombed factory, Motor Sich, is one of many firms requisitioned by the Ukraine government since Moscow’s invasion.

Motor Sich is located near Khmelnytskyi in western Ukraine, around 300km (190 miles) southwest of Kyiv.

The region, home to a major Ukrainian airbase, has been regularly targeted by Russian strikes in recent months.

During his evening speech, Zelenskiy maintained a strong stance, emphasising that regardless of the frequency of Russian attacks, they will not yield any advantages for the enemy.

Prior to this, on Saturday, Ukraine reported the destruction of a Russian tanker, the Sig, which was transporting fuel for Russian troops, as informed by a Ukrainian security source to AFP.

The attack occurred around 11:20 pm (20:20 GMT) on Friday, south of the Kerch Strait, according to Russia's Federal Agency for Sea and Inland Water Transport.

The ship sustained damage to its waterline in the region of the engine room but remained afloat, as stated by the agency.

A video, purportedly showing the attack, was obtained by AFP. In the video, a vessel is seen approaching a larger ship before the footage cuts off.

The Ukrainian source disclosed that the operation, which involved a naval drone and explosives, was executed in collaboration with the navy within Ukrainian territorial waters. This operation was labelled as a "successful special operation."

The Sig oil and chemical tanker is under US sanctions for providing jet fuel to Russian forces in Syria, who are backing President Bashar al-Assad.

The Russian foreign ministry condemned the assault on what it termed a "civilian vessel," adding that the crew remained unharmed.