GENEVA — In remarks to the Human Rights Council on Thursday, U.N. High Commissioner for Human Rights Michelle Bachelet said Israeli forces may have committed war crimes in their 11-day assault on the Gaza Strip.

Israeli airstrikes killed at least 248 in Gaza, including 66 children and 39 women, before a ceasefire was announced last weekend. In Israel, 12 people also died, including two children.

Bachelet said Hamas’ retaliatory rocket fire during the violence was also a clear violation of the rules of war, NBC reported.

“Air strikes in such densely populated areas resulted in a high level of civilian fatalities and injuries, as well as the widespread destruction of civilian infrastructure,” Bachelet said, adding that “such attacks may constitute war crimes”, if deemed to be indiscriminate and disproportionate in their impact on civilians.

Bachelet urged Israel to ensure accountability, as required under international law in such cases, including through “impartial, independent investigations” of actions in the escalation.

She criticized Hamas for locating military assets in densely populated civilian areas and firing rockets from them.

“These rockets are indiscriminate and fail to distinguish between military and civilian objects, and their use, thereby, constitutes a clear violation of international humanitarian law,” Bachelet said. “However, the actions of one party do not absolve the other from its obligations under international law.”

The remarks came during a day-long special session for the U.N.’s top human rights body to discuss the “the grave human rights situation” in Gaza, the West Bank and east Jerusalem.

The Organization of Islamic Conference presented a resolution that, if passed by the council, would authorize the council to set up a permanent commission to report on human rights violations in Israel, Gaza and the West Bank, a move criticized by Israel.

During the session, Riad al-Maliki, the Palestinian foreign minister, highlighted years of suffering by Palestinians in the lands controlled or occupied by Israel.

“The Israeli war machinery and terrorism of its settlers continue to target our children who face murder, arrest and displacement, deprived of a future in which they can live in peace and security,” he said.

Bachelet also pointed to “root causes” of the violence in the region, saying “it will certainly be a matter of time until the next round of violence commences with further pain and suffering for civilians on all sides.”