A Russian rocket attack Thursday destroyed a cafe and grocery store in Hroza, Ukraine, killing at least 51 civilians, according to Ukrainian authorities.

Ukranian Interior Minister Ihor Klymenko stated on Telegram that a six-year-old child was among the dead in Hroza, a village of around 300 people. The search and rescue mission continues into Friday, as rescuers and forensic scientists sort through the debris and identify those killed.

Civilians endangered by armed conflicts are protected by Geneva Convention IV, adopted in 1949. Article 4 of the convention defines protected people as “those who at a given moment and in any manner whatsoever, find themselves, in case of a conflict or occupation, in the hands of a Party to the conflict or Occupying Power of which they are not nationals.” Article 32 prohibits the murder and torture of protected persons. Similarly, Articles 51 and 52 of the Protocol One to the Geneva Conventions prohibit the targeting of civilians and civilian objects. Russia and Ukraine are both parties to the treaty and the protocol. However, in 2019 Russia withdrew its declaration recognizing the competence of the International Humanitarian Fact-Finding Commission to investigate violations of the protocol.

On Thursday, President of Ukraine Volodymyr Zelenskyy attended a summit of the European Political Community and gave a speech, calling on other European leaders to take action. Later in the day, he gave another speech in which he called the Russian attackers “absolute evil.” He also said:

Russian terror must be defeated. And the world has the means to ensure this. The key is unity. The key is believing in freedom and protecting lives. Today, our main message to the world is: evil cannot prevail. And only now, only in Ukraine, can this principled moral position be maintained. But together, all together!

UN High Commissioner for Human Rights Volker Türk expressed feeling “shocked and saddened” by the attack, which he said was “one of the deadliest in 20 months.”