Large numbers of children are starving to death in Niger because food aid is being misdirected, says France's Medecins Sans Frontieres (MSF).
Disease is adding to the dangers now facing children
An average of 40 young children are dying each day in one area in the east of the country, a new study has found.
International relief was sent to the west African nation when the plight of millions was first highlighted in July.
The World Food Programme says it has dispatched food for 1.3 million, with extra supplies for the most vulnerable.
And, along with help from the Niger government and other NGOs, the first round of aid distribution is not far from completion.
Up to three million of Niger's 12 million population are estimated by the UN to be suffering food shortages.
Some 32,000 children with severe malnutrition face death without the necessary food and medical treatment, the UN has said.
'Insufficient and inadequate'
But MSF says specialised food aid is not reaching those in the most extreme stages of starvation - it is being directed instead at the moderately malnourished.
Some areas in the eastern Zinder province have seen no aid at all, says the BBC's Hilary Andersson.
One feeding centre in Zinder for children "between life and death" received 1,000 new patients last week alone, said MSF spokesman Christian Captier.
"The aid is still insufficient and inadequate. It is not targeting the right population at the moment," he told the BBC.
An estimated 1,500 children died in one of area of the province in August alone.
Although millions of dollars worth of aid is now in the country, the situation had visibly worsened in areas our correspondent first visited in July.
Malaria has now set in and many of the starving are now struggling to fight disease in their weakened condition, our correspondent found.
The World Food Programme has rejected claims the aid is being misdirected, saying special supplies for the most vulnerable were airlifted in July and extra provisions are provided for families of children being treated at feeding centres.
Meanwhile, journalists have found evidence that social structures may be partly to blame for the crisis, with men locking away food stores when they leave their villages for any length of time.