Wednesday, leaders in Ukraine's Donbas area urged more than 300,000 inhabitants to leave to safety ahead of an anticipated Russian military operation as Moscow attempts to gain ground in the war-ravaged country's east.

Wednesday, the leader of the Donetsk region, one of two that comprise the Donbas, asked for the evacuation of the remaining 350,000 inhabitants. After Moscow declared victory in the Luhansk province, the other half of the Donbas, an escalation of the Russian offensive was anticipated.

Pavlo Kyrylenko, the governor of Luhansk, stated that the evacuations would allow Ukrainian forces to focus on defending the region against increasing attacks.

According to The Guardian, Kyrylenko stated that Donetsk would determine the entire country's fate. Once the population decreases, we can focus more on the enemy and accomplish our primary objectives.

Wednesday saw a severe bombardment of the Kramatorsk area city of Sloviansk by Russian forces.

"Russian forces from the Eastern and Western Groups of Forces are likely now around [10 miles] north from the town of Sloviansk," the British Defense Ministry, which has been monitoring the conflict since its inception, said in a statement.

As the town is also threatened by the Central and Southern Groups of Forces, there is a severe potential that the war for Sloviansk will be the next decisive engagement in the Donbas conflict.

Since April, when it refocused its forces and operations on eastern Ukraine, Moscow has achieved gradual but steady military progress. Years ago, pro-Russian separatists populated the Donbas and opposed the Kyiv administration.

According to Ukrainian military sources, Russia controls approximately 55 percent of the Donetsk region. Still, Moscow's pace may be speeding after its victories in Lysychansk and Severodonetsk during the past few weeks, and both were significant Ukrainian strongholds in the Donbas region.

CNN quotes Vadym Liakh, chairman of the Slovyansk military-civilian administration, as saying, "Those who saw [what happened in Severodonetsk or Lysychansk] left a long time ago,"

"Around 23,000 people remain in Slovyansk out of a population of approximately 100,000. The number of individuals eager to depart has risen. We are coordinating evacuations in two directions: Lviv, Dnipro, and Rivne."

According to Ukrainian President Volodymyr Zelenskyy, an air warning sounded throughout Tuesday night and Wednesday morning, spreading concern among the populace.