"I have to announced that, unfortunately, we have lost more heroes," wrote Maxim Kozitsky, governor of the Lviv region. "35 people died as a result of the shelling of the International Peacekeeping and Security Centre."
The base is used as a training centre for Ukraine's military and has been a centre for joint exercises with NATO. Foreign instructors are regularly present but it's unclear if any were there at the time of the attack.
Located close to the Polish border, Lviv has become a gateway point for those fleeing the country and has previously escaped the attacks seen in other parts of the country.
The capital city Kyiv is bracing for an imminent attack by Russian forces, who are now believed to be encircling the city.
"The Russian invaders cannot conquer us," President Volodymyr Zelensky wrote on social media. "They do not have such strength. They do not have such spirit. They are holding only on violence. Only on terror."
The Ukrainian authorities have said the city of Mariupol, which is now under Russian control, is facing a humanitarian catastrophe. Citizens have lost access to water and heating, and are rapidly running out of food.
"Mariupol is still surrounded," the French military announced. "That which they cannot have by war, (the Russians) want to have by hunger and despair. Since they cannot bring down the Ukrainian army, they target the population."
The Russian military has itself admitted the severity of the situation in Mariupol.
"Unfortunately, the humanitarian situation in Ukraine is continuing to deteriorate rapidly, and in some cities, it has reached catastrophic proportions," confirmed Mikhail Mizintsev, head of the Russian National Defence Control Centre.
