As the US military withdraws from Afghanistan, it is leaving behind a deadly legacy of about 2,000 square kilometres of land littered with undetonated grenades, rockets and mortar shells.
The military has abandoned scores of firing ranges infested with the explosives. Dozens of children have been killed or wounded as they have stumbled upon the sites, which are often poorly marked.
And casualties were likely to increase sharply as the United States military had removed the munitions from only 3 per cent of the territory covered by its sprawling ranges, officials said.
Clearing the rest of the contaminated land — which is almost twice the size of Hong Kong — could take up to five years.
US military officials say they intend to clean up the ranges, but because of a lack of planning, officials say, funding has not yet been approved for the monumental effort, which is expected to cost US$250 million.
"Unfortunately, the thinking was 'We're at war and we don't have time for this'," said Major Michael Fuller, the head of the army's mine action centre at Bagram Airfield, referring to the planning.
There are a growing number of tragedies at these high-explosive ranges.
Mohammad Yusef, 13, and Sayed Jawad, 14, grew up 100 metres from a firing range used by US and Polish troops in Ghazni province. The boys' families were accustomed to the thundering explosions from military training exercises, which sometimes shattered windows in their village.
But as those blasts became less common with the US and Nato withdrawal, the boys started wandering on to the range to collect scrap metal to sell. They did not know that some US explosives did not detonate on impact but could still blow up when someone touched them.
Last month, Jawad's father, Sayed Sadeq, heard a boom and ran on to the range, where he spotted his son's bloodied torso.
"The left side of his body was torn up. I could see his heart. His legs were missing," the father said.
One of the boys, it appeared, had stepped on a grenade. Both boys died.
"If the Americans believe in human rights, how can they let this happen?" Sadeq asked.
Since 2012, the UN mine action co-ordination centre of Afghanistan has recorded 70 casualties in and around US or Nato firing ranges or bases, and the pace of the incidents has been increasing.
But the statistics don't paint a complete picture, with The Washington Post finding 14 casualties who were not included in the UN data, including the two boys.
Most of the victims were taking their animals to graze, collecting firewood or searching for scrap metal. Of the casualties recorded by the UN, 88 per cent were children.
Top US military officials say they intend to remove the explosives from the ranges.
"It will take time and expense to complete this work, but it's critical to the safety of the Afghan people and it is the right thing to do," said Edward Thomas, a spokesman for General Martin Dempsey, the chairman of the US joint chiefs of staff.
But even if the Congress approves the hundreds of millions of dollars in clean-up costs, it will be extremely complicated to remove the munitions.
The US closed down more than half of its 880 bases in Afghanistan and withdrew the bulk of its troops before creating a plan to remove the unexploded munitions, one American official said. In some areas, there was nobody left to provide security.
"There are less people to identify sites," the US official said. "And then if you decide you want to do the right thing and get them out there, how do you do it? Who protects them?"