GAZA/JERUSALEM - At least 45 Palestinian civilians, including 29 from Gaza City, were killed Saturday by Israeli gunfire and shelling in various parts of the Gaza Strip, the official WAFA news agency quoted medical sources as reporting.

Palestinian officials reported widespread destruction in residential areas, a rising death toll and mounting pressure on hospitals as the Israeli military expanded its operations in Gaza City, warning residents to leave.

Gaza's Civil Defense agency accused Israel of targeting schools sheltering displaced people and crowded residential buildings, killing dozens and wounding hundreds. In a statement, it said the army was seeking to empty the city through "comprehensive destruction."

Also in the day, the Hamas-run Gaza government media office said in a statement that since the start of its ground offensive on Aug 11, the Israeli army has destroyed more than 1,600 residential buildings and 13,000 tents for displaced families, forcing over 350,000 people to flee from eastern Gaza City to central and western areas.

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It said major neighborhoods, including Shuja'iyya, Zaytoun, Tuffah, Rimal, and Sheikh Radwan, were facing systematic destruction, which it called a violation of international humanitarian law.

Israeli army spokesman Avichay Adraee stated on Saturday that more than 250,000 residents had left Gaza City "for their safety." He urged civilians to use Al-Rashid Street to head to the "humanitarian zone" in Al-Mawasi in southern Gaza or to "empty areas" in central Gaza. He said Gaza City has become "a dangerous combat zone" and that the army is determined to defeat Hamas there.

The Israeli military had struck a high-rise building in Gaza City on Saturday, saying it housed Hamas command and control centers used to target Israeli forces.

The Israel Defense Forces (IDF) said that within the building, Hamas established military infrastructure used to advance and execute attacks against IDF troops in the area. It provided no immediate evidence to support the claim. Hamas has previously rejected such allegations, calling them "fabricated pretexts" for attacks on civilian infrastructure.

WAFA news agency said Israeli airstrikes destroyed the Al-Noor Tower in Tel al-Hawa, a multi-storey residential building sheltering displaced families.

The IDF said it took measures to limit civilian casualties, including advance warnings to residents, precision-guided munitions, aerial surveillance, and intelligence assessments prior to the strike.

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The attack follows a wave of similar strikes on high-rises in Gaza City in recent weeks, as Israel intensifies its ground and air offensive against Hamas in the territory's largest city. In previous incidents, residents reported receiving less than an hour to evacuate before strikes.

On Friday, the IDF said it had hit more than 500 Hamas targets across Gaza City in the past week, including sniper positions, tunnel entrances, weapons caches, and other militant infrastructure.

WAFA reported a surge in Israeli bombardment across northern Gaza on Saturday, with strikes on residential buildings and towers in Gaza City. It said several civilians were wounded when warplanes hit a house on Al-Thawra Street in the Al-Rimal neighborhood, while drones targeted homes near Al-Yarmouk.

The agency also reported Israeli armored vehicles firing on Palestinians queuing for humanitarian aid in central Gaza, though the IDF had no immediate comment.

Ahmed al-Farra, head of the pediatric department at Nasser Medical Complex in Gaza, warned Saturday of severe shortages of medical equipment and therapeutic foods. He told Xinhua that the number of malnourished children has exceeded the hospital's capacity and that deaths are expected to rise.

The United Nations Relief and Works Agency for Palestine Refugees in the Near East (UNRWA) described the situation in Gaza City as "catastrophic."

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"Airstrikes are ongoing everywhere, including without prior warning. Almost every moment, a home is bombed. It is terrifying," UNRWA said in a statement. "People have nowhere to go. ... There is no safe place. This war must stop."

The war began Oct 7, 2023, when Hamas fighters rampaged through southern Israel, killing 1,200 people and taking around 250 hostages, according to Israeli tallies. Israel's subsequent campaign in Gaza has killed nearly 65,000 Palestinians, according to the enclave's health authorities.