Demining teams from at least nine international organizations have begun a coordinated sweep of the Iran-Iraq border zone and the western approaches to the Strait of Hormuz, officials said Wednesday, as a sharp rise in civilian casualties from unexploded ordnance threatens to outpace what humanitarian agencies had budgeted for in the first month of the post-war response.

The U.N. Mine Action Service, citing field reports collected through Tuesday evening, said it had recorded 71 deaths and 218 injuries from unexploded munitions across Iran, Iraq, Yemen and southern Lebanon since the April 15 ceasefire took effect. More than half of those casualties were children, and the agency said the daily figure was rising rather than falling — a pattern it attributed in part to displaced families returning to villages faster than survey teams could clear them.

“What we feared in the first week is what we are now seeing,” said Helene Voss, the deputy head of UNMAS operations in Baghdad, in a video briefing from the agency’s regional coordination cell. “People are walking back into communities that have not been swept. Children are picking up objects in fields. We are losing time, and we are losing lives.”

The agency identified three categories of munition driving the casualty count. Submunitions from cluster-type weapons used in the war’s middle weeks remain scattered across agricultural land in Iran’s Ilam and Kermanshah provinces and across the Khuzestan-Basra crossing corridor. Failed Iranian ballistic missile components, some of which fell in populated areas during interception failures, have been recovered as far north as Erbil. And a number of Houthi-launched rocket fragments and Israeli air-delivered munitions have been documented along the Yemeni Red Sea coast and in southern Lebanese villages.

In the Iranian border town of Mehran, which served as a primary reception point for tens of thousands of displaced families during the war and is now functioning in reverse, local Red Crescent volunteers said they had begun escorting returnees through marked routes only, with families instructed not to leave designated paths. “We are walking people through their own streets like guides,” said Reza Karimi, a volunteer coordinator with the Iranian Red Crescent Society, by phone from Mehran. “Most of them understand. Some of them do not understand why their own home is now a danger.”

The U.S.-backed HALO Trust, which has operated in northern Iraq for more than two decades, said it had redirected nearly its entire staff from previously planned legacy clearance work, much of it dating to the Saddam Hussein era and the Islamic State conflict, toward the most recently contaminated districts. The Norwegian People’s Aid mission said it was bringing in additional technical staff from its Balkans operations and expected to field roughly 180 surveyors and clearance technicians in Iran and Iraq combined by the end of next week.

Iranian state media reported that the country’s own mine-clearance bureau, which has historically focused on legacy contamination from the 1980-1988 Iran-Iraq war, had been authorized to coordinate directly with international agencies for the first time in more than a decade. A senior Iranian Interior Ministry official, quoted by the semi-official IRNA news agency, said Tehran would accept “any technical assistance that does not carry political conditions.” Western diplomats said the formulation was deliberately permissive and indicated that the Iranian government understood the scale of the contamination problem exceeded its domestic capacity.

The funding picture remains uncertain. The U.N.’s revised flash appeal issued on April 17 included $185 million earmarked specifically for survey and clearance work, but as of Wednesday only about a fifth of that figure had been pledged, according to figures circulated to donor capitals. The European Commission has indicated it will likely meet a portion of the gap through its humanitarian aid instrument, but officials in Brussels cautioned that disbursement timelines could stretch into June.

“This is the part of the response where speed matters most and money is hardest to find,” said Layla Hassan, a Beirut-based regional analyst who has tracked post-conflict recovery in the Levant for nearly two decades. “Every donor wants to fund reconstruction visible from a press conference. Demining is invisible until somebody dies on television.”

The casualty pattern has begun to shape return policy. UNHCR on Tuesday revised downward its projection of returns through May, citing the contamination risk along with continued utility outages, and asked Iranian and Iraqi authorities to continue staggering the reopening of interior districts. The Iraqi Ministry of Migration and Displaced, which had been pushing to accelerate returns to Basra and southern Anbar, agreed Wednesday to maintain its current phased schedule for at least another two weeks.

The picture in Yemen remains the most opaque, partly because access to former Houthi front-line areas has been limited and partly because pre-existing contamination in the country makes it difficult to separate war-era munitions from older ones. The International Committee of the Red Cross said its teams in Hodeidah had begun preliminary marking of suspected hazard zones around the port and along the coastal highway running south toward Mokha.

In southern Lebanon, where Hezbollah-controlled districts absorbed Israeli strikes in the war’s middle weeks, Lebanese army engineers began their own survey work on Sunday with technical support from a French military advisory team that had remained in country after the ceasefire. Lebanese officials said priorities included school grounds and the approaches to two hospitals in the southern suburbs of Beirut.

UNMAS and partner agencies said they were preparing a joint public information campaign aimed at children, to be distributed through schools, mosques and community radio in Farsi, Arabic and Kurdish. The first materials were expected to reach distribution points in Iran and Iraq this weekend.

Officials said a fuller damage and contamination assessment would be presented to donor governments at a coordination meeting in Geneva early next month.