At Nasser Hospital's morgue in southern Gaza, workers envelop the bodies of those killed in Israeli airstrikes with white cloth amid the overpowering scent of death.
They document essential details about the deceased, such as their name, identity card number, age and sex.
Badly mutilated bodies are stored in the morgue's refrigerator for weeks, with only those identified or claimed by relatives eligible for burial and inclusion in the Gaza Health Ministry's death toll for the war.
The ministry's death toll has drawn international attention to the high number of civilians killed in the Israeli military's offensive, launched after Hamas' Oct. 7 incursion on Israel, the bloodiest in the country's 75-year history.
The toll stood at 20,057 people as of Friday morning, amid renewed international calls for a fresh cease-fire in Gaza.
The ministry says thousands more dead remain buried beneath the rubble.
About 70% of those killed are women and children, it says.
However, with most hospitals across Gaza closed, hundreds of doctors and health workers killed, and communications hampered by a lack of fuel and electricity, it is becoming increasingly difficult to compile casualty figures.
The morgue workers at Nasser Hospital are part of an international effort, including doctors and health officials in Gaza, as well as academics, activists, and volunteers worldwide, to ensure the toll doesn't become a casualty of the increasingly dire conditions of the war.
The workers, some volunteers, do not have enough food or water for their families, but they persist because recording the number of Palestinians dying matters to them, said Hamad Hassan Al Najjar.
He mentioned the psychological toll of the work, holding a piece of white paper with handwritten information about one of the dead, often shocked to find the badly damaged corpse of a friend or relative brought in.
The body of the morgue's director, Saeed Al-Shorbaji, and several family members arrived in early December after they were killed in an Israeli airstrike, according to Al Najjar.
"He was one of the pillars of this morgue," said Al Najjar, his face worn with sadness and fatigue. Preparing the bodies of dead children, some missing heads or limbs, was the most painful task: "It takes you hours to recover your psychological balance, to recover from the effects of this shock."
The Israel Defense Forces (IDF) have expressed regret for civilian deaths but blamed Hamas, the Palestinian group that ran the Gaza Strip, for sheltering in densely populated areas.
Hamas members killed 1,200 people in the Oct. 7 attack, most of them civilians, and seized some 240 hostages.
Israel says it will continue its offensive until Hamas is eliminated, the hostages returned, and the threat of future attacks on Israel removed.
An Israeli military spokesperson, in response to a comment request for this article, said the IDF "follows international law and takes feasible precautions to mitigate civilian harm."
U.N. vouches for the data
The data recorded by Al Najjar and his colleagues is collated by workers at an information center set up by the health ministry at Nasser Hospital in the city of Khan Younis.
Ministry staff fled their offices at Al-Shifa Hospital in northern Gaza after Israeli forces entered it in mid-November.
Ministry spokesperson Ashraf Al-Qidra, a 50-year-old doctor, reads the numbers at press conferences or posts the figures on social media if communications are hampered by the hostilities.
The head of the ministry's information center did not respond to requests for comment.
Since early December, the ministry has said it has been unable to collect regular reports from morgues at hospitals in northern Gaza, amid the collapse of communication services and other infrastructure due to the Israeli offensive.
According to the World Health Organization (WHO), only six of Gaza's 36 hospitals were receiving casualties as of Wednesday, all of them in the south.
The WHO cited this as one reason it believes the ministry's tally may be an undercount; the toll also excludes dead who were never taken to hospitals or whose bodies were never recovered.
The WHO and other experts said it was not possible for now to determine the extent of any undercounting.
U.S. President Joe Biden said on Oct. 25 he had "no confidence" in the Palestinian data. The ministry's figures say nothing about the cause of death, and they do not distinguish between civilians and Hamas members.
Following Biden's remark, the ministry released a 212-page report listing 7,028 people killed in the conflict until Oct. 26, including identity cards, names, age, and sex.
The United Nations, which has a long-standing cooperation with Palestinian health authorities, continues to vouch for the quality of the data.
The WHO noted that, compared to previous conflicts in Gaza, the figures show more civilians have been killed, including a greater proportion of women and children.
Israeli officials this month said they believe the data released to date is broadly accurate; they have estimated that one-third of those killed in Gaza are Hamas members, without providing detailed figures.
The Palestinian Health Ministry, located in the occupied West Bank and paying the salaries of Gazan ministry workers, said it has lost almost all contact recently with hospitals in the enclave.
It also has no information on the fate of several hundred health workers arrested by Israeli forces, it added.
Asked about the arrests, the IDF said it had detained some hospital staff based on intelligence that Hamas was using medical facilities for its operations.
Those not involved in these activities were released after questioning, it said, without providing the number of detainees.
International efforts
Academics, advocates, and volunteers across Europe, the United States, and India are working to analyze the data provided by the Gaza Health Ministry, to corroborate the details of those killed and determine the numbers of civilian casualties.
Much of this is based on the Oct. 26 list, which includes names, identity card numbers, and other details.
Some other researchers, meanwhile, are "scraping" social media to preserve accounts posted there for future analysis.
"There are far more eyes and players involved in recording Gaza deaths than is normal and than exist in the world's other worst crises," said Leslie Roberts, Professor Emeritus of Population and Family Health at Columbia University's Mailman School of Public Health.
Roberts has been involved in more than 50 mortality surveys during wars since the early 1990s.
London-based Airwars, a non-profit affiliated with the Department of Media and Communications at Goldsmiths, University of London, that investigates civilian deaths in conflicts, is using social media and the ministry's Oct. 26 document to compile a detailed record of casualties.
Airwars director Emily Tripp said some 20 volunteers were working on the project alongside regular staff, and so far, it has positively identified some 900 civilians killed in the fighting.
Even if the fighting stopped today, it could take another year to finish the survey, she said.
"What we are also seeing now is civilians who've been killed who are displaced from other areas, so they are not easily identified by their neighbors," Tripp told Reuters. "That makes the process of counting and identification really challenging."
Zeina Jamaluddine, a doctoral student at the London School of Hygiene and Tropical Medicine, co-authored an analysis last month in the Lancet medical journal based on the health ministry's Oct. 26 list.
The study concluded that the identification numbers of those listed as killed were highly correlated with age, a pattern unlikely to arise from data fabrication.
She said the Palestinian health authorities' systems for collecting data had been tested over multiple wars and revised through United Nations-backed efforts: "While no data is 100% perfect, Palestine has high-quality data."
While excess mortality experts have tools for calculating total deaths after conflicts end, there are challenges to doing so, and the final post-war toll could end up being incomplete unless deaths are recorded to the greatest extent possible in real-time, she said.
"Every name on the list represents a person, a life, or a story. Each one deserves to be remembered."
Family annihilation
Researchers use methods such as surveys of households after a conflict is over to estimate the overall toll.
Household surveys could be difficult following this conflict because, in some cases, entire families have been killed by bombardments – sometimes dozens of members, according to the Oct. 26 list.
More than four-fifths of Gaza's pre-war population has fled their homes – 1.9 million people, according to U.N. figures – and may be difficult to locate, experts say.
But given how close-knit Gazan society is, there is hope that such studies could eventually be conducted in a meaningful way, said Hamit Dardagan of the Iraq Body Count (IBC), an organization that records violent deaths resulting from the 2003 U.S.-led invasion of Iraq.
The IBC has already published an analysis of the age and other characteristics of those killed in Gaza, based on the ministry's Oct. 26 data.
"The pace of civilian deaths – at least 200 each day since Oct. 7, except for the week-long truce – is unprecedented this century and was not seen at the height of the Iraq invasion," Dardagan said.
It will take years to recover the remains of people from beneath the rubble, and the costly, technical process will not result in the identification of each body, said Dr. Gilbert Burnham, a doctor and professor at Johns Hopkins University who has worked since the 1970s on humanitarian health problems in wars.
In addition to the dead, the ministry says there have been more than 52,500 people wounded in the conflict.
The WHO points to the growing risk of disease due to a lack of clean water, food, and medical attention.
Dr. Ghassan Abu Sitta, a British-Palestinian surgeon who volunteered in two hospitals in northern Gaza for the first six weeks of the war, said some people were dying because of the lack of treatment for open wounds.
"The death toll is a poor proxy for human suffering," said Dr. Annie Sparrow, a pediatrician who has worked with medics treating the wounded in the Syrian civil war for more than a decade and is an Associate Professor of Global Health at the Icahn School of Medicine at Mount Sinai in New York City.
But the use of records to fight the fear of erasure runs deep in Palestinian culture, said Abdel Razzaq Takriti, associate professor of Modern Arab History at Rice University in Texas. He quoted from a poem by prominent Palestinian poet Mahmoud Darwish: "You will be forgotten as if you never were."
Takriti said many Palestinians see the Gaza war as part of a history of conflict and displacement by Israeli forces dating back to the Nakba, or catastrophe in Arabic when more than 700,000 Palestinians fled or were expelled from their homes in what is now Israel during the war over the formation of the country in 1948.
"For the sake of the present, future, and the past, we need to have an accurate rendition of numbers," Takriti said.