Doctors at one of Gaza City's last functioning hospitals say they are overwhelmed with casualties from Israeli strikes and are having to carry out operations in filthy conditions with few or no anaesthetics.

One Australian medic volunteering at al-Shifa hospital told the BBC that every day was a mass casualty event, while another described how a baby had been saved from the body of a pregnant woman who had been killed.

Israeli forces are now just 500m (1,640ft) away from the hospital as they expand their ground offensive to fully occupy Gaza City, which Israel's military calls Hamas's main stronghold.

Witnesses say tanks are advancing into the city centre from the south and north-west.

Israeli air and artillery strikes, attacks by quadcopter drones and detonations of remotely driven vehicles laden with explosives continue to drive tens of thousands of Palestinians from their homes each day. The Israeli military says it is carrying out the offensive in Gaza City to defeat Hamas and secure the release of hostages still held by the group after 23 months of war.

Al-Shifa hospital was once the biggest medical complex in the Gaza Strip. It now lies in ruins, pockmarked by craters, with burned-out wards and bullet holes.

Inside, medics are working beyond full stretch with many beds lacking mattresses, a shortage of medicines, and an endless stream of casualties. It's just a mass murder, a killing, a torture, a nightmare, said Dr. Nada Abu Alrub, reflecting on the conditions within. Emergency consultations have become routine, with operations performed under extreme duress and inadequate anaesthesia, leading to heartbreaking outcomes.