Mounds of trash rotting in the heat are piling up close to where displaced people are sheltering in Gaza, a UN official has said, raising fears about the further spread of disease, Al Jazeera reports.

Louise Wateridge, an aid worker with United Nations Palestinian refugee agency (UNRWA), said that a pile of waste weighing an estimated 100,000 tonnes was building up near people’s tents in central Gaza.

“It’s among the population and it’s building up without anywhere to go. It just keeps getting worse. And with the temperatures rising, it’s really adding misery to the living conditions here,” she told journalists via video link from Gaza.

Israel has refused repeated requests to allow UNRWA to empty the main landfill sites, she said, meaning temporary ones are emerging, she added.

Even if permission is granted, Wateridge said UNRWA’s humanitarian missions such as trash collection have all but halted due to Israeli refusals to allow fuel imports.