The Israeli army razed three buildings on Sunday, killing at least 26 people, and injuring 50 others, according to the Gaza Health Ministry.
Among the victims are 10 women and eight children.
It is the deadliest attack since heavy fighting broke out between Israel and Hamas leaders in Gaza in nearly a week.
Rescue teams continue to try to remove survivors and bodies from the rubble.
Israel bombed the home of the top Hamas leader in Gaza early Sunday in another attack, according to the army.
It was the third such attack targeting the homes of Hamas leaders in the past two days.
The army said it attacked the homes of Yehiyeh Sinwar, the top Hamas leader within the territory, and his brother Muhammad, another senior Hamas member.
On Saturday, it destroyed the home of Khalil al-Hayeh, a senior member of Hamas's political wing.
Brigadier General Hidai Zilberman confirmed on Army radio the attack on Sinwar's home in the southern Gaza city of Khan Younis.
The army spokesman said that the house of Sinwar's brother, who is in charge of Hamas "logistics and personnel," was also destroyed.
The Hamas leadership has gone into hiding in Gaza, and it is unlikely that anyone was at home at the time of the attacks.
Hamas's top leader, Ismail Haniyeh, splits his time between Turkey and Qatar, countries that lend political support to the group.
Hamas and the Islamic Jihad militant group have acknowledged the deaths of 20 fighters since fighting broke out on Monday, while Israel claims the actual number is much higher.
In the latest attacks - the worst since the 2014 Gaza war - at least 174 Palestinians have been killed in Gaza, including 47 children and 29 women, according to data from the Health Ministry.
Eight Israelis have died, including a 5-year-old boy and a soldier.
Hamas and other militant groups have fired some 2,900 rockets at Israel since Monday, when tensions flared.
While Israel has carried out hundreds of airstrikes across the impoverished and blockaded territory, which is home to more than 2 million Palestinians.
Early on Sunday, Israeli warplanes attacked several buildings and roads in the center of Gaza City.
Photos released by residents and journalists showed that the airstrikes had caused a crater blocking one of the main access roads to the Shifa hospital, the strip's largest medical center.
Israel stepped up attacks in recent days to inflict as much damage on Hamas as possible while accelerating efforts to negotiate a ceasefire.
A US diplomat is in the region to try to defuse tensions, and the UN Security Council will meet on Sunday.
Since the conflict began, Israel has razed several of the tallest residential and office buildings in Gaza City, claiming they house Hamas military infrastructure.
On Saturday, he headed to the 12-story Al Jalaa building, where the offices of AP, the Al Jazeera television network and other media are located, as well as several apartment floors.
"The campaign will continue as long as necessary," Israeli Prime Minister Benjamin Netanyahu said in a televised speech on Saturday, claiming that Hamas military intelligence was operating inside the building.
After the attack on the building that housed the offices of several international media, the Secretary of State of the United States, Antony Blinken, spoke by phone with the president and CEO of The Associated Press, Gary Pruitt and offered his support to the journalists. independent and media organizations.
With information from AP.