“Reading the health experts, I am starting to think with horror that if it’s not stopped, Israel’s assault could end up exterminating almost the entire population in Gaza over the next couple of years,” Francesca Albanese, UN Special Rapporteur for Palestine, wrote on Friday on social media.

Albanese cited a recent report from University of Edinburgh global public health chair Devi Sridhar finding that the true death toll from Israel’s genocide could be estimated at 335,500 as of September.

Sridhar based this rough calculation off of an estimate by public health researchers published in The Lancet in July regarding typical indirect death counts from previous conflicts, citing research hailed as the gold standard in the field. At that time, the researchers estimated that the true death toll could be roughly 186,000, stemming from direct killings like bombings as well as Israel’s destruction of the health, food and sanitation systems in Gaza.

The death toll, then, could be between 15 and 20 percent of the population by the end of this year, Albanese said, in just over a year of Israel’s genocide. And, as Sridhar writes in her Guardian report, the calculation that she borrows from The Lancet editorial is highly conservative — meaning the death toll could be even higher than her 335,500 estimate.