Israeli strikes on Gaza’s southern city of Rafah killed 22 people and wounded dozens, local health officials said on Monday, after US President Joe Biden told Israel not to attack Rafah without a credible plan to protect civilians.

Heavy bombing caused widespread panic in Rafah as many people were asleep when the strikes started, said residents contacted by Reuters using a chat app. Some feared Israel had begun its ground offensive into Rafah.

The Israeli military said on Monday it had conducted a “series of strikes” on southern Gaza that have now “concluded,” without providing further details.

Before previous assaults on Gaza cities, Israel’s military has ordered civilians to leave without preparing any specific evacuation plan.

Biden told Prime Minister Benjamin Netanyahu on Sunday that Israel should not launch a military operation in Rafah without a credible plan to ensure the safety of the roughly 1 million people sheltering there, the White House said.

Aid agencies say an assault on Rafah would be catastrophic. It is the last relatively safe place in an enclave devastated by Israel's military offensive.

Biden and Netanyahu spoke for about 45 minutes, days after the US leader said Israel’s military response in the Gaza Strip had been “over the top” and expressed grave concern over the rising civilian death toll in the Palestinian enclave.

Hamas militants killed 1,200 people in southern Israel and abducted at least 250 in their October 7 incursion, according to Israeli tallies. Israel has responded with a military assault on the Gaza Strip that has killed more than 28,000 Palestinians, according to the Hamas-run health ministry.

Hamas-run Aqsa Television on Sunday quoted a senior Hamas leader as saying that any Israeli ground offensive in Rafah will “blow up” the hostage-exchange negotiations.