The United Nations Mine Action Service (UNMAS) says that the mammoth task of clearing Gaza’s debris is made all the more costly and dangerous by the sheer amount of asbestos and unexploded ordnance.

Nearly seven months into the war, UNMAS estimates the amount of debris in the Gaza Strip at 37 million tons in mid-April, or 300 kilograms per square meter, Al Jazeera reported. 

“Gaza has more rubble than Ukraine, and to put that in perspective, the Ukrainian front line is 600 miles (nearly 1,000 kilometers) long, and Gaza is 25 miles (40 km) long,” said Mungo Birch, head of the UNMAS program in the Palestinian territories.

But the volume of rubble is not the only problem, UNMAS said.

“This rubble is likely heavily contaminated with UXO (unexploded ordnance), but its clearance will be further complicated by other hazards in the rubble,” Birch told journalists in Geneva.