Hundreds of individuals died in an explosion at a hospital in Gaza City, which Hamas claims was brought on by an attack by Israel.
When the attack occurred, the al-Ahli Hospital in Gaza City was crowded with injured Palestinians and those looking for safety.
Although the death toll has not been verified, it might exceed 500.
The Israeli Defence Force has refuted accusations that it was behind the attack on the Gaza hospital.
According to a spokeswoman for Israel, the incident was carried out by the smaller militant organisation Palestinian Islamic Jihad (PIJ), which is based in the Gaza Strip.
"The entire world should know: It was barbaric terrorists in Gaza who attacked the hospital in Gaza, not the IDF," Israeli Prime Minister Benjamin Netanyahu declared.
The hospital explosion was described as "a horrific massacre" by Hamas.
Tuesday night, a top Palestinian official announced his resignation in protest of the claimed Israeli airstrike on the hospital.
The Red Cross described itself as "shocked and horrified" by the situation.
The World Health Organisation (WHO) said it "strongly condemns" the occurrence.