Ukrainian nationals living in Japan have spoken of their anxiety following Russia's invasion of their country, including concern about family members and friends back home struggling through fear and sleepless nights.

"My elderly mother is unable to see very well. It would be hard for her to move around, and I wonder if there will be a place for her to evacuate," said Olena Kryvoruka, 42, who runs a music school in Asahikawa, Hokkaido in northern Japan, after Russia launched its invasion Thursday.

People from Ukraine stage a protest rally in Tokyo's Shibuya area on Feb. 24, 2022, following Russia's military attack on Ukraine. (Kyodo) ==Kyodo

As tensions escalate, with Russian troops approaching the capital Kyiv and having taken control of the Chernobyl nuclear power plant in the north, Ukrainian Ambassador to Japan Sergiy Korsunsky on Friday expressed his anger over the level of casualties in his homeland.

Ukrainian Ambassador to Japan Sergiy Korsunsky. (Kyodo)

At a press conference in Tokyo at the Foreign Correspondents' Club of Japan, Korsunsky lamented how troops attacked "a peaceful country without any provocation" with missiles "in peaceful time."

He said the Russian forces who have seized the plant, known for the 1986 nuclear disaster, "have absolutely no idea how to monitor it, how to manage it," and expressed fears that radioactive contamination could spread to the whole of Europe.

Sharing the fears of her compatriots, Kryvoruka said she cannot think of anything else now beyond the situation in her homeland, saying that she fears many civilians will fall victim if they attempt to resist the invasion.

She recounted her family's experience in 2014, when Russia annexed Crimea from Ukraine, a former Soviet republic, and Ukrainian government troops and pro-Russian separatists clashed. She said a bomb fell 5 meters away from their home in Luhansk, prompting her parents to move to Kyiv.

She believes that the aggression will not stop unless tougher sanctions by the United States and Europe are imposed on Russia.

Tokyo resident Serhii Korennov also expressed his worries over the safety of his family.

The 49-year-old, who has lived in Japan since 1996, said that he called his older sister based in Kyiv via videophone hours after Russia launched the invasion. His sister, 64, told him that she "heard a big explosion nearby."

Thinking of the poor health of his 85-year-old mother, who lives alone, he said, "I am worried whether she can escape if the worst comes to the worst." He had promised his sister and mother that he would see them in April for the first time after three years.

"If something happens to my family, I'll regret it forever. I wish I had gone to meet them earlier," he said.

Several dozen Ukrainians as well as their supporters gathered on Thursday evening in front of the busy Shibuya scramble crossing, a Tokyo landmark, to protest the invasion.

At the popular waiting spot, participants who assembled in the social media-organized protest held Ukrainian flags and posters reading "Stop War."

People from Ukraine stage a protest rally near the Russian Embassy in Tokyo on Feb. 23, 2022. (Kyodo)

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