At least 1 million, or 10 lakh, people have fled Ukraine due to the “senseless war”, United Nations High Commissioner for Refugees Filippo Grandi said on Thursday.

“I have worked in refugee emergencies for almost 40 years, and rarely have I seen an exodus as rapid as this one,” Grandi said in a statement. “Hour by hour, minute by minute, more people are fleeing the terrifying reality of violence. Countless have been displaced inside the country.”

The exodus began on February 24 when Russia began its offensive on Ukraine. On that day, more than 82,000 people fled the former Soviet country, reported Al Jazeera. In just seven days, more than 2% of Ukraine’s population of 44 million, or 4.4 crore, have left the country.

United Nations refugee agency spokesperson Joung-ah Ghedini-Williams told the Associated Press that according to figures collected by national authorities, the refugee count crossed 1 million mark on Wednesday midnight.

Shabia Mantoo, another spokesperson for the agency, said that “at this rate” the exodus from Ukraine could make it the source of “the biggest refugee crisis this century”.

In his statement, the agency’s chief said that millions more will be forced to leave Ukraine if the conflict is not brought to an end.

Grandi noted that despite this mass exodus, other countries have been “remarkable” in receiving these refugees. He said that the agency’s staff were also assisting the refugees and supporting the host governments in the task.

“International solidarity has been heartwarming,” he said. “But nothing – nothing – can replace the need for the guns to be silenced; for dialogue and diplomacy to succeed. Peace is the only way to halt this tragedy.”

At least 227 civilians have been killed and 525 injured in Ukraine since the invasion began, the figures from the United Nations agency’s office showed.

The agency said that it used strict methodology and was counting only confirmed casualties, but admitted that the figures are undercounted.

After over 82,000 people left on the first day of the Russian invasion, at least 1.17 lakh new refugees have fled the conflict-hit country each day. On Tuesday, the single-day exodus hit its peak of nearly 2 lakh, according the United Nations.

In comparison, after the civil war had erupted in Syria in 2011, about 5.7 million, or 57 lakh, people had fled the country, the agency’s figures showed. But even when the exodus from Syria had increased rapidly in 2013, it took at least three months for 1 million refugees to leave the Western Asian country, according to Al Jazeera.

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