International aid organization Doctors Without Borders says it hasn’t heard from medical staff stationed in the Shifa hospital in Gaza since Saturday, when staff reported they were trapped amid fighting between Israeli and Hamas forces near the complex.

Doctors Without Borders, also known as Medecins Sans Frontieres (MSF), is an independent organization that offers medical humanitarian assistance in regions across the world where medical aid is scarce or added support is needed.

“Since last night, we have not been able to contact our staff inside Al-Shifa hospital,†the organization , formerly Twitter, on Sunday. “Other MSF colleagues living in Gaza city reported that the hostilities around Al-Shifa have not stopped. We are worried for their lives.â€

The Shifa hospital complex is the biggest health facility in Gaza where MSF staff are still actively working.

On Saturday, from Dr. Mohammed Obeid, an MSF surgeon stationed in the hospital, who said that the situation is “very bad.

"Our team is exhausted. We have two neonate patients who died, because the incubator is not working, because there is no electricity.â€

An MSF nurse, meanwhile, sent a text from the hospital on Saturday, , describing how he and his family were sheltering from bombing in the hospital’s basement.

“My kids are crying and screaming in fear,†the text reads.

Read more: Heavy fighting rages near main Gaza hospital and people trapped inside say they cannot flee

The Associated Press reported that the hospital’s last generator ran out of fuel Saturday, according to the Health Ministry in Gaza, leading to the deaths of three premature babies and four other patients.

Israel has said that it placed 300 litres of fuel near Shifa overnight for the hospital and that they would be helping to move babies from the facility on Sunday, claims which health officials in the hospital have rejected. Speaking to CNN, Israeli Prime Minister Benjamin Netanyahu asserted that "100 or so" people had already been evacuated from Shifa.

MSF staff on the ground people are alleging that people attempting to flee the hospital are being fired upon, according to MSF's Saturday statement.

"There are a lot of patients already operated on and they cannot walk," Obeid said in the statement. "They cannot evacuate. We need an ambulance to move them, we don't have ambulances to evacuate all of these patients.â€

Netanyahu has said Israel will not consider a ceasefire until the nearly 240 hostages captured by Hamas in the Oct. 7 attack have been released.

At least 1,200 people have been killed on the Israeli side, most of them civilians killed in the initial attack. More than 11,000 Palestinians have been killed since the war began, according to the Health Ministry in Gaza.

Earlier in the week, MSF posted a statement urging the Canadian government , adding that the health system in Gaza is failing due to “unimaginable duress," and that they believe the term "humanitarian pause," which Canada has endorsed, is not sufficient. 

With files from the Associated Press