Israeli warplanes resumed pounding Gaza, Palestinian civilians fled for shelter, and rocket sirens blared in southern Israel on Friday as the week-old truce ran out with no deal to extend it. The seven-day pause that ended late on Thursday had allowed for the release of hostages and facilitated the entry of aid into the shattered coastal enclave. As the deadline lapsed, mediator Qatar said it was trying to reach a new agreement that would extend the pause, possibly by expanding it to include Israeli men as well as women. But the resumption of fighting has raised the stakes in the bitter conflict that has killed more than 3,000 people.

The renewed strikes sent tens of thousands of people streaming from their homes along the main Salah al-Din Road into the interior, where they hoped to find safe havens. Families packed whatever they could carry and headed west down the highway, with children waving white flags. Some were told they had to leave their cars, which Israeli soldiers blocked.

Among the first airstrikes on Friday, a large building in Khan Younis was destroyed. A witness saw rescuers clawing through rubble in a bid to find survivors. At least 32 Palestinians were killed across the Gaza Strip in the first hours after the ceasefire ended, the health ministry said.

As the bombs fell, Israeli ground forces pushed deeper into the enclave in what Israel says is a campaign to destroy Hamas and its tunnel networks. The army has advanced into northern and central Gaza, destroying hundreds of homes and displacing more than 1.7 million people, according to the United Nations agency that helps the displaced, UNRWA.

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Israel’s refusal to negotiate a renewed truce and its continued bombardment of the crowded enclave has sparked an outpouring of anger from civilians. In a rare move, the U.S. ambassador to the United Nations, Samantha Power, joined international critics of Israel’s behavior in an open letter addressed to the country’s prime minister.

The letter was accompanied by a petition signed by more than 13,000 people urging the government to do more to protect civilians in Gaza, including by extending the week-old ceasefire. It also urges the international community to increase pressure on Israel to do more to help the Palestinian people in Gaza.

Intense overcrowding and deteriorating hygiene have triggered a rapid rise in disease, with diarrhea, chickenpox, and scabies among the most prevalent. The WHO warns that younger children and immunocompromised adults are particularly at risk.

As the fighting raged, the UN envoy to the Middle East, Nickolay Mladenov, called for “a quick and unconditional return to the negotiating table.” But there were no signs that either side was ready for such a meeting, with Israel insisting it is in a war to defeat Hamas, while Palestinians say Israel is trying to drive them into the sea. The fighting has drawn in the world’s major powers and prompted criticism of both sides.