A string of big explosions rocked Ukraine moments after Russian President Vladimir Putin announced the beginning of a "special" military strike in Kyiv and other cities where millions of civilians reside.

Ukraine's foreign minister Dmytro Kuleba called Russia's operation "a full-scale invasion" and "a war of aggression" as Moscow troops attacked "peaceful" Ukrainian areas.

However, President Putin noted that the operation's goal was not to invade but to demilitarize Ukraine. He also wanted the people behind "multiple bloody crimes against civilians," including Russian citizens, to face justice, per Reuters.

Residents across Ukraine trembled as buildings shook from constant explosions. The bombings killed at least eight people, according to initial reports from Kyiv.

Explosions were seen in Kharkiv just minutes after President Vladimir Putin announced a military operation in eastern Ukraine, as reported by The New York Times.

Kharkiv, the country's second-largest city with more than 1.4 million residents and the closest major city to the Russian border, has been rattled by blasts that prompted some residents to hide.

A civilian apartment complex in Chuhiv neighboring Kharkiv, also got hit by a blast. As of present writing, the number of casualties is still unknown.

Ukraine's military reported four Russian tanks were destroyed on the road near Kharkiv, 50 personnel were killed near a village in the Luhansk area, and six Russian aircraft were shot down in the east.

Russia has dismissed claims that its planes or armored vehicles had been downed. Separatists backed by Russia claim to have shot down two Ukrainian planes.

Kyiv now. Russians will never be forgiven for this. The last time similar scenes were witnessed in the Ukrainian capital was during the attack of Nazi Germany in WWII pic.twitter.com/g421yinG55

— Olga Tokariuk (@olgatokariuk) February 24, 2022

US and Its Allies are Ready To Respond

Following the reported explosions, President of the United States Joe Biden expressed sympathy to the people of Ukraine who faced "unprovoked and unjustified attack" from Russia. As a result, he and other Western leaders have pledged harsh sanctions on Moscow, saying that the US and its allies will answer in a "united and decisive" manner.

Biden also announced that the US helped Ukraine and NATO allies to strengthen their forces. The Pentagon has already placed around 8,500 US troops on high alert to augment NATO's response force.

Britain's UN envoy accused Russia of keeping Ukraine hostage and urged Russia to avoid conflict, claiming that it would have a "devastating" humanitarian impact of both nations losing many lives.

According to CNet report, UK Ambassador Barbara Woodward noted during an emergency meeting of the UN Security Council that Russia has been "holding a pistol to Ukraine's head" in recent months, and the time has come that Putin's "finger is on the trigger." She said that the world's appeal for peace only fell on Russia's deaf ears.

Read Also: US Official Sees Russia 'Beginning' Its Invasion, But Ukraine's Economy Already Suffers Due to 'Hybrid War' 

Ukrainians Prepared To Fight

Ukrainian President Volodymyr Zelensky posted on Twitter that Russia "treacherously" attacked his country like what the "Nazi Germany did in WW2 years."

"As of today, our countries are on different sides of world history. Russia has embarked on a path of evil, but Ukraine is defending itself & won't give up its freedom no matter what Moscow thinks," Zelensky said.

Moreover, he encouraged Ukrainians to rally on the streets to defend the country as weapons would be provided to those who were ready for combat. Zelensky also calls on the Russian people to protest against their government's aggression.

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