Since the fighting started on October 7, about 40,000 buildings, or around 18% of all pre-conflict structures, have been damaged or destroyed in the Gaza Strip, according to a U.N. assessment released on Tuesday.

Following the deadly cross-border strikes by the dominant Islamist group in the enclave, Hamas, on October 7, Israeli forces launched an aerial and ground offensive against the organization in Gaza. As a result, about 1.9 million people, or around 85% of the population, have left their homes.

The latest estimate, based on a Nov. 26 image, was produced by the United Nations Satellite Centre, where analysts examine very high resolution satellite images to find damaged buildings and publish maps that can guide relief work and rebuilding plans during natural disasters and conflicts.

Estimates such as this based on high-resolution satellite images might still under-estimate the scale of destruction since they do not show all building damage – for example, a collapsed building with an intact roof can look undamaged.