The collapse struck Niscemi, near the coastal city of Gela, where saturated hillsides gave way following a powerful storm system. The rupture stretches for roughly four kilometres, carving a sheer new cliff through residential areas. Vehicles and buildings were swept more than 20 metres downhill, while dozens of homes remain precariously suspended above unstable ground.
Environmental groups say the disaster highlights years of underinvestment in climate preparedness and risk reduction.
Campaigners argue that national energy policies continue to prioritise fossil fuel infrastructure over measures designed to protect communities, warning that such choices are amplifying vulnerability across the country. They are calling for large-scale, long-term investment in climate mitigation and adaptation, from northern regions to the south.
Emergency crews have established a 150-metre exclusion zone around the most affected areas, declaring entire streets uninhabitable. Civil protection officials say parts of the hillside are still shifting, making any return impossible for many families.
"The slope is continuing to move towards the Gela plain," one senior emergency coordinator said, adding that authorities are now working with local leaders to secure permanent housing solutions for displaced residents.
Earlier this week, the government placed Niscemi under a wider state of emergency covering three southern regions hit by the same storm system, releasing an initial €100 million in relief funding. Regional authorities estimate that damage across Sicily alone may reach €2 billion.
Prime minister Giorgia Meloni said the first tranche of aid was intended to meet immediate needs, promising further financial support in the weeks ahead.
Geologists note that Niscemi sits on layers of sand and clay that become highly unstable during prolonged rainfall — a vulnerability exposed before, most notably in a 1997 landslide that forced hundreds to evacuate. The latest collapse has reignited criticism over past building decisions on land long known to be at high risk.
The debate comes amid mounting concern over how climate change is intensifying pressure on fragile landscapes throughout Sicily. Scientists point to a warming Mediterranean as a key factor behind increasingly violent storms affecting the island.
Environmental advocates warn that without steep cuts in greenhouse gas emissions, rising sea levels could permanently reshape Italy's coastline by the end of the century, with thousands of square kilometres of low-lying land at risk — much of it home to dense populations.
"We can't go on tallying destroyed homes and lost lives while these events are brushed off as routine weather," said one climate campaigner. "The science is clear, and political inaction is pushing communities towards ever more devastating outcomes."
Opposition figures have urged the government to redirect funding from large infrastructure projects towards emergency preparedness and climate resilience, while conservation groups say recent storms underline how extreme weather and land-use pressures are becoming the country's new normal.
They are calling for faster implementation of adaptation measures, particularly in regions exposed to landslides, flooding and coastal erosion — warning that without decisive action, disasters like Niscemi will only become more frequent.