A 5-year-old was among eight children killed by an Israeli airstrike on a Gaza refugee camp early Saturday, Palestinian officials said, marking one of the deadliest incidents since the long-running conflict between Israel and Hamas reignited earlier this week.

Two adults also were killed when a home was hit in the Al-Shati refugee camp to the west of Gaza City, according to the Palestinian Health Ministry.

Mohammed Hadidi told reporters his wife and five children had gone to celebrate the Eid al-Fitr holiday with relatives, according to the Associated Press. She and three of the children, aged 6 to 14, were killed, while an 11-year-old was missing, he said. Only his 5-month-old son Omar was known to have survived.

With fears of all-out war running high, U.S. diplomat Hady Amr arrived Saturday in the Israeli city of Tel Aviv where sirens rang out signaling incoming barrages of Hamas rockets. Hady is due to meet with senior Israeli and Palestinian officials to push for calm.

However, missile bombardments showed no signs of slowing. Air-raid sirens wailed in Israeli cities to herald incoming rocket fire from Gaza. One rocket hit a neighbourhood in central Israel’s Ramat Gan, where raw footage showed fire and debris in the streets. The Magen David ambulance service said one man died at the scene.

Meanwhile, Israel’s military continued to unleash strikes on the Gaza Strip.

The latest chapter in the conflict between Israel and Hamas, the militant group governing Gaza, was triggered by unrest in Jerusalem. Since Monday, Hamas has fired more than 2,300 missiles into Israel and Israel’s military has unleashed a barrage of strikes on Gaza, with tanks and artillery joining aerial attacks, according to officials.

At least 129 Palestinians including 39 children have been killed in Gaza. In Israel, nine people have been killed. Hundreds have been wounded on both sides.

While the clashes were largely restricted to Gaza, they spread to the West Bank on Friday and health officials said 11 people died Friday and more than 250 were injured.

Intercommunal violence, meanwhile, has swept several cities and neighborhoods in Israel. Scenes of vigilante mobs administering beatings and hurling stones have unsettled the nation and sparked appeals for calm, but showed no signs of abating. Police said 15 people were arrested in the city of Lod overnight for involvement in riots, while a number of rioters also were arrested in East Jerusalem.

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Palestinians on Saturday are set to mark Nakba Day, which commemorates the displacement of hundreds of thousands of people during Israel’s creation in 1948. Demonstrations in support of their cause are also planned in several cities around the world, including London and Berlin.

Israel’s Prime Minister Benjamin Netanyahu had warned Friday that more attacks would come, saying Hamas “attacked our capital, they sent missiles to our city, they pay a heavy price for it.”

The Israeli military has called up 9,000 reservists and massed troops along its border with Gaza. While there was alarm and confusion late Thursday after the Israeli military announced “ground troops” were attacking the area, the military later clarified that its forces where within its country’s borders.

The Associated Press contributed to this report.