Israeli forces say they are expanding their military operations in southern Gaza.

The Israeli military's spokesperson Daniel Hagari said on Sunday that its troops are uncovering tunnels and killing Hamas fighters in Khan Younis. He said they will continue to step up operations in the coming days.

Hagari also announced the deaths of 10 Israeli soldiers.

Also on Sunday, health authorities in Gaza said an Israeli air strike killed at least 70 people at the Maghazi refugee camp in central Gaza.

A video posted on social media by the Palestine Red Crescent Society shows rescue operations by its teams. Some people are believed to be trapped under debris.

Reuters news agency says many of the victims were women and children.

Health authorities denounced the attack, calling it a massacre committed in a crowded residential area.

Israel's military told CNN that it is reviewing reports of an incident at the camp. The military said it is "committed to international law, including taking feasible steps to minimize harm to civilians."

Israeli Prime Minister Benjamin Netanyahu vowed to continue the fight against Hamas "until the end."