Hospitals in central Gaza have reported that 40 people were killed in two Israeli airstrikes overnight within a few hundred meters of each other.
Al Aqsa hospital said it had received 29 bodies from one strike, nine of whom were children, while Al Awda hospital said it had received 11 bodies after the second strike.
The strikes occurred at about 1 a.m. and 2:45 a.m. on Tuesday morning local time (6 p.m. and 7:45 p.m. Monday EDT), according to witnesses.
Rescue workers have continued efforts to find bodies underneath the rubble of a four-story building in Nuseirat that was demolished in the first strike. Witnesses said dozens of people had been sheltering in the building鈥檚 yard.
CNN video showed those injured and killed being brought into Al Aqsa Martyrs Hospital, while other video shows the bodies of several children being retrieved from the wreckage.
Desperate family members surround the piles of rubble, waiting to see if anyone is rescued alive, the footage showed. But the workers at the scene clearly lack equipment to remove the concrete.
CNN has reached out to the Israel Defense Forces for comment on the two strikes.
Some of those killed had recently arrived from Rafah, according to people at the scene.
One witness, Ashraf Al Jalees, told CNN at the site: 鈥淚 swear these are innocent civilians 鈥hey are all buried under the ground, including children. There are seven girls here. What fault did they have?鈥
He said he had set up a tent for a friend 鈥 Hassan Obeid 鈥 whom he said had 鈥渘o affiliation with Hamas or anyone else.鈥
Calling out Obeid鈥檚 name, Al Jalees added: 鈥淗e stayed to sleep here tonight, and the house collapsed on all of them 鈥 Over 50 people are under this, I swear to God they are all innocent civilians. God will question me one day if I am lying.鈥
Another man, Hamdan Karaja, told CNN: 鈥淢y children, both girls and boys, are under the rubble. My wife as well.鈥
Karaja said he had seven children. He said the body of his father had been retrieved.
鈥淲e have over 100 displaced individuals, with some comprising 20 family members. They are all trapped under the rubble. We were targeted while we were asleep, without any prior warning,鈥 he said.
鈥淲e also have displaced people鈥檚 tents in the yard. We have 10 martyrs here and 20 over there.鈥
Rami Al Aida, a Civil Defense spokesperson in Central Gaza, said crews were 鈥渙perating in extremely challenging conditions due to a lack of fuel and equipment. We hope to find people alive. We appeal to all international organizations to provide the Civil Defense with the necessary tools, bulldozers, and fuel.鈥
Al Aida agreed with the assessment of others at the site that dozens were still under the rubble. 鈥淭here are over four families trapped under the rubble, in addition to the displaced families seeking shelter in and around the building. There are more than 100 people.鈥
A girl who gave her name as Sama Alousha said they had heard a detonation at about 1 a.m.
鈥淲e all panicked and came to see what happened. I saw my friend鈥檚 house completely destroyed. We are unable to rescue anyone. I have five friends trapped under this place.鈥
One unnamed man said he and his family had been displaced several times.
鈥淲e were displaced from Shajaiya. We moved to Khan Younis and then to Rafah, and from Rafah, we came here. My brother rented a place here and stayed there with his family.
鈥淪uddenly, I received a call informing me that the place where my brother was staying was hit. There are no tools to retrieve them. They are a family of six, all innocent civilians. My brother, his wife, and four children.鈥
He then called out the names of his brother鈥檚 family, but there was no response.
One tearful woman at the scene, Um Mahmoud, told CNN: 鈥淢y brother arrived from Rafah three days ago after being forcibly displaced, and now we do not know his whereabouts. He, along with his wife and five children, has no connections with anyone. He is simply a displaced person who came from Rafah and was still searching for a place to stay in Deir el Balah.
鈥淗is name was on the list of those supposed to leave Gaza through the Rafah border, but fate intervened,鈥 she added.
A man called Salah Abu Jarada said his brother had also come from the Rafah area. 鈥淭hey were hit, with three floors collapsing on top of them. They have not been rescued yet.鈥
A second strike occurred at the UNRWA school in Nuseirat about two hours after the first, according to witnesses.
Ismail Abu Ghosheh said: 鈥淓verything is burnt, and seven people were killed.鈥
Another man at the school, Najah Abu Daher, said: 鈥淭here is no safe place to go. They follow us wherever we go. My son was killed, along with three of my relatives. They struck us in the dead of night, causing children to run everywhere and glass to shatter.鈥