UN Commissioner for Human Rights Michelle Bachelet Wednesday said that Russia may have committed war crimes through its “indiscriminate attacks” on civilians and hospitals. These are Bachelet’s strongest words yet on the conflict and come shortly after the UN appointed human rights experts to probe possible war crimes in Ukraine.

In her address to the UN Human Rights Council in Geneva, Bachelet noted the “persistent use” of explosives with wide-area effects such as missiles, airstrikes, and heavy artillery shells and rockets in populated areas is of “immense concern.” There are credible allegations that Russia has used cluster munitions at least 24 times in such areas. Additionally, Bachelet’s office is investigating allegations of cluster munition use by Ukrainian forces.

Civilians and non-military targets such as homes, hospitals, schools, and administrative buildings were attacked using these weapons. Bachelet stated that there had been 77 verified incidents where medical facilities were damaged, and at least 1,189 civilian deaths since the Russian invasion began on February 24. The actual numbers are expected to be much higher as “it is very challenging to obtain a comprehensive picture” in locations of intense hostility, like the port city of Mariupol. Additionally, the Human Rights Monitoring Mission have corroborated reports of further incidents.

Bachelet said that these “indiscriminate attacks” are prohibited under international humanitarian law and “may amount to war crimes.” The large-scale destruction of non-military targets and the high civilian casualty rate strongly indicates the “fundamental principles of distinction, proportionality and precaution have not been sufficiently adhered to” by Russian forces.

As the worsening humanitarian crisis and “immeasurable suffering” in Ukraine approaches its sixth week, Bachelet implored Russia to listen to the “clear and strong calls of the General Assembly and this Council, and immediately act to withdraw its troops from Ukrainian territory.”