Some media reports say at least 100 Palestinians and 13 Israeli soldiers were killed on Sunday, May 16.  

The United Nations Security Council was set to hold an emergency meeting on the Gaza situation at 0130 GMT Monday, following a call by Palestinian President Mahmoud Abbas, as regional leaders met in Doha for urgent ceasefire talks.

According to some sources, the Palestinian death toll soared to 438 in the bloodiest single day in Gaza in five years, with a spokesman for the enclave's emergency services saying more than a third of the victims were women and children.

The Israeli army reportedly said 13 soldiers had been killed inside Gaza on the third day of a major ground operation, bringing to 18 the number of soldiers killed since the ground operation was launched late on Thursday.

It reportedly was the largest number of Israeli soldiers killed in combat since the 2006 Lebanon war.

The Associated Press (AP) says a league of Muslim nations on Sunday demanded that Israel halt attacks killing Palestinian civilians amid heavy fighting between it and Hamas in the Gaza Strip, even as fissures between countries over their recognition of Israel emerged.

A statement by the 57-nation Organization of Islamic Cooperation reportedly hewed closely to previous ones issued by the Saudi-based group, including backing the decades-old call for Palestinians to have their own nation with East Jerusalem as its capital.

“The massacre of Palestinian children today follows the purported normalization,” Iranian Foreign Minister Mohammad Javad Zarif said.  “This criminal and genocidal regime has once again proven that friendly gestures only aggravate its atrocities.”

The Organization of Islamic Cooperation statement called on Israel to respect Muslims' access to Al-Aqsa Mosque, the third-holiest site in Islam, as well as stop settlers from forcibly evicting Palestinian families from their homes.

“The plight of the Palestinian people is the bleeding wound of the Islamic world today,” Afghan Foreign Minister Mohammad Haneef Atmar said.

But the videoconference meeting reportedly saw some delegates instead turn their fire toward countries like Bahrain, Morocco, Sudan and the United Arab Emirates, Muslim nations which reached normalization deals last year to recognize Israel.  While Egypt and Jordan earlier reached peace deals, supporters of the Palestinians criticized the new countries for recognizing Israel before the formation of an independent Palestinian state.

AP notes that the past week has seen some of the worst violence across Israel and the Palestinian territory since the 2014 war in Gaza, with militants launching missiles and Israel pounding the blockaded coastal strip home to 2 million people with heavy fire.  At least 188 Palestinians have been killed in Gaza with 1,230 people wounded.  Eight people in Israel have been killed, according to AP.