Al Shifa Hospital was once the largest and most advanced medical facility in Gaza.
Now it has become a battleground in the Israel-Hamas war. Israeli soldiers seized the hospital on 15 November.
They are searching for what they say is a Hamas headquarters hidden underground - a claim that Hamas and hospital staff have repeatedly denied.
After the 7 October attacks, Israeli Prime Minister Benjamin Netanyahu vowed to eliminate Hamas. The bombardment of the Gaza Strip began.
Sky News has traced the path of the deadly conflict as it reached the hospital gates.
Using military footage, satellite imagery and open-source intelligence, we created a 3D model of the tunnels under the hospital to try to answer a key question:
What lies beneath al Shifa Hospital?
"One of the most horrific scenes I witnessed in al Shifa was after the air raid when the dead and wounded were brought in.
"Medical staff would frantically look at their faces 鈥� in many cases their children would be among them."
EARLY ATTACKS
Israel's military claimed that it was responsible for the ambulance attack referenced above, saying that it was "being used by a Hamas terrorist cell".
At least 15 people were killed and 60 others were injured, according to the Hamas-controlled health ministry. But the chaos outside al Shifa's walls quickly reached inside the hospital complex, as the model below illustrates.
'A DEATH ZONE'
Palestinians inspect al Shifa Hospital after Israeli troops moved into the building
Palestinians inspect al Shifa Hospital after Israeli troops moved into the building
Human suffering within al Shifa escalated to the point that the World Health Organization branded it a "death zone".
With a shortage of medical resources and an overwhelmed emergency department, doctors were driven to desperate measures. British-Palestinian surgeon, Dr Ghassan Abu Sittah, described what happened when he ran out of antiseptic solution.
"I started using washing up liquid then vinegar to clean the wounds."
Dr Ghassan Abu Sittah
Dr Ghassan Abu Sittah
"You felt you were in quicksand where you had more and more difficult decisions based on availability rather than clinical need."
Dr Abu Sittah made the difficult decision to leave the hospital during the evacuation.
"I will fight until [my patients] receive the treatment they need and the justice they deserve. My heart is broken in ways I never knew was possible," he wrote of his departure in a post on X (formerly Twitter) on 19 November.
'NOT A BATTLEGROUND'
Hospitals have special protections under international rules of war and are generally protected from attacks.
On 15 November, UN aid chief Martin Griffiths wrote on X that he was "appalled" by the news of "military raids" at al Shifa because "hospitals are not battlegrounds".
Israel claims that al Shifa sits on top of a Hamas HQ and said this was its reason for military action inside the compound.
"Before you can attack a hospital, even if you think that they've lost their protection, you have to issue a warning and provide time for the opposing party to cease its misuse of the facility," said Brian Finucane, an expert legal adviser for the non-partisan International Crisis Group.
Israel Defence Forces (IDF) international spokesperson, Lieutenant Colonel Peter Lerner, said on 19 November that Israeli forces had not ordered an evacuation of the hospital. He said the army had agreed to a request from the hospital's director for those wanting to leave to evacuate through a "secure route".
Lt Col Peter Lerner
Lt Col Peter Lerner
Mr Finucane said it was not clear from the available evidence when, or if at all, al Shifa had lost its protection under the rule of law.
Speaking to Sky News on 22 November, he said: "We simply don't have enough information to draw any confident legal judgments at this time."
A VAST NETWORK
Tunnels used by Hamas within the Gaza Strip are thought to stretch across hundreds of miles.
The group has repeatedly denied using hospitals, including al Shifa, as a shield for its operations.
Israeli claims regarding Hamas's alleged presence in the hospital are not entirely new.
During a 2008-2009 war, Israel accused the Palestinian group of using underground areas of the hospital to hide - which they denied.
Zvi Elhyani holds the archives of the Israeli architect who redesigned the hospital in the 1980s.
Mr Elhyani, a Tel Aviv-based architecture expert, said in an article for Israeli media site Ynetnews: "It's a little-known fact that the iconic structure, which has gained international recognition and drawn considerable attention, was designed by Israeli architects... during the 1980s."
Former Israeli prime minister Ehud Barak told CNN that Israel had built bunkers "decades ago" underneath the hospital.
We do not know where these basements are located in the complex.
In October, the IDF published a 3D illustration purporting to show the extensive subterranean infrastructure they believe exists beneath al Shifa.
The White House has said its independent intelligence supported Israel's claim that Hamas was using Gaza's hospitals, including al Shifa, to hide command posts.
ISRAEL'S EVIDENCE
In the early hours of 15 November, the Israeli army entered al Shifa Hospital.
The IDF said that its forces were carrying out a "precise and targeted operation against Hamas" at the hospital and the intention was not to harm civilians.
Since seizing the compound, the IDF has published a series of pictures and videos of what it says is evidence of Hamas's presence operating in the hospital grounds and underneath it.
The compound is currently controlled by the Israeli military. The lack of independent access to the site has limited the visual evidence available. The analysis below is based on information Sky News has been able to independently verify.
DOWN THE SHAFT
A video posted on 16 November was the IDF's first visual evidence of a tunnel at Shifa.
Sky News analysed further IDF videos and created a 3D model based on the evidence so far. We verified information using satellite imagery, open-source intelligence, and interviews.
The entrance to the shaft, seen in the footage, was found near a truck which the IDF says was booby-trapped, along with dozens of weapons and ammunition.
It was under a white building visible in the previous video posted by the Israeli army on 15 November.
Based on historical satellite imagery, we know that the white building was completed on 6 July 2021 - we don't know what it was used for.
Below shows two low-resolution satellite images of the same location. No building is present on 5 July 2021, but a day later the white building is visible. It appears in all satellite images after this date.
Additional video of the same tunnel posted in the following days offered more insight.
QUESTIONS REMAIN
The evidence provided so far, as verified by Sky News, proves the existence of a tunnel under the hospital, along with rooms of around 50 square metres.
Sky News has not been able to independently verify who constructed the tunnel or whether it was used by Hamas.
The image below shows a Hamas tunnel (left) pictured in 2014 and a screenshot (right) taken from IDF footage filmed inside a tunnel underneath al Shifa.
Left: A Hamas fighter in a Gaza tunnel in 2014 (Reuters pic). Right: A screenshot from IDF footage in a tunnel underneath al Shifa.
Left: A Hamas fighter in a Gaza tunnel in 2014 (Reuters pic). Right: A screenshot from IDF footage in a tunnel underneath al Shifa.
The arched roof of the corridors seen in IDF footage underneath al Shifa is similar in shape and design to Hamas tunnels, which have been pictured elsewhere in the Gaza Strip in previous years
Dr Ana Heitor, a lecturer in geotechnical engineering at Leeds University, said that it was likely the tunnel was "hand or manually excavated" using demolition power tools. Her judgement was based on the ground material, the width of the tunnel and its inconsistent geometry.
The rooms seen in footage inside the tunnel do not contain weapons. IDF spokesperson Rear Admiral Daniel Hagari said in a video inside the tunnel that he believes one of the rooms was cleared before the army entered.
"This room was evacuated. All the gear was evacuated I guess... when they knew we were going to enter Shifa hospital."
An Israeli soldier stands in a room inside a tunnel underneath al Shifa Hospital
An Israeli soldier stands in a room inside a tunnel underneath al Shifa Hospital
Israel says Hamas had "sealed" parts of the tunnel prior to the army's entry to the hospital.
The footage of a room directly underneath the surgery building shows two orange steel beams in the ceiling.
The beam is seen in IDF footage posted on 22 and 27 November
The beam is seen in IDF footage posted on 22 and 27 November
Dr Heitor told Sky News that she believes the main function of the beam is to support the ceiling rather than part of the foundation of the building.
But the video provided a limited view and has not been independently examined, she added.
On 23 November, al Shifa hospital's director, Dr Muhammad Abu Salmiya, was arrested by the IDF over evidence the military said showed the facility had been used by Hamas.
Those allegations have been denied by both Hamas and by hospital staff.
"At no stage did I ever see anyone carrying a personal weapon," Dr Abu Sittah said. "There were no signs of militarisation.
"It was barely functioning as a hospital let alone as some great command and control centre."
Dr Mads Gilbert, a Norwegian anaesthetist who has regularly worked at al Shifa since 1989, also said that he has never seen any armed Palestinians at the hospital.
"These are normal medical staff, smart people 鈥� researchers, professors, PhDs. They鈥檙e dedicated to the patients."
Dr Gilbert, who is currently in Egypt, awaiting clearance to return to Gaza with a group of medics funded by the Norwegian government, says that al Shifa would usually see thousands of patients pass through its doors every week.
"It's not just the largest health facility in Gaza, but the flagship for healthcare in Palestine."
A temporary truce in Gaza has now ended after Israel accused Hamas of breaking the ceasefire agreement.
Eight weeks ago al Shifa was a major, functioning hospital. Two weeks ago, it was a place of refuge. Now, it is nearly empty.
A satellite image taken on Sunday shows the courtyard which was once covered by tents and full of civilians, almost bare.
All but a few patients have left, along with most of the hospital's staff.
The Israeli army is continuing to search the site for evidence of Hamas's presence, including the alleged command and control centre.
HOW WE BUILT THE MODEL
Sky News pored over dozens of images and videos from the hospital - before, during and after the Israeli offensive.
A scale model of the hospital's buildings was constructed in SketchUp by combining satellite images with footage from news agencies and social media. Google Earth Pro was used to get measurements of key features, which were then used as reference points for the more detailed elements visible in on-the-ground footage.
Drone footage of the entrance to the tunnel shaft was used to ascertain its location and orientation. Pillars visible near the surface were used to determine the direction of the tunnel leading from the base of the shaft.
Within the tunnel, distances and the dimensions of rooms were calculated using a variety of methods including counting tiles and slabs on the walls, the size of which were estimated relative to the height of IDF soldiers.
CREDITS:
Writing and reporting: Olive Enokido-Lineham, OSINT producer; Ben van der Merwe, data journalist; Michelle Inez Simon, visual investigations producer
Production and modelling: Ben van der Merwe, data journalist; Michelle Inez Simon, visual investigations producer; Michael Drummond, foreign news reporter; Matt Chapman, data scientist; Giacomo Boscaini-Gilroy data visualisation journalist
Editing: Adam Parker, OSINT editor; Natasha Muktarsingh, assistant output editor; Serena KutchinAG百家乐在线官网, assistant editor; Chris Howard, editor
Design: Taylor Stuart and Phoebe Rowe, designers; James Packer, senior designer
Pictures: Reuters, Associated Press, IDF handouts