'Dozens of children die' in Nigerian lead poisoning
As many as 30 children have died of lead poisoning in northern Nigeria over the past week, authorities believe.
Scores of people - mostly children - have already died this year in Zamfara state, poisoned by lead-contaminated waste from illegal gold mining.
The latest deaths occurred in a remote village near the town of Anka.
But officials have not been able to confirm the reports because rainy-season downpours have prevented them from getting to the area.
Lead poisoning has killed at least 160 since June, when visiting doctors realised children in the region were dying in unusually large numbers.
Investigating scientists traced the source of the poisoning to soil contaminated with lead which had been dumped in water sources by miners.
For weeks in June teams worked to try to decontaminate a number of villages, by scraping away topsoil.
But experts at the time said that many more children would be affected by the slow-acting poison.
There are fears that the rains may have washed the poison back into wells and other water sources.
In their attempts to extract gold, deadly amounts of lead were released - it is thought that soil containing lead deposits was dumped in water sources and in places where children played.
The deaths were discovered during the country's annual immunisation programme, when officials realised that in several villages there were virtually no children.
Villagers said the children had died of malaria and it was only when a team from international aid agency Medecins Sans Frontieres took blood tests from local people that the high concentrations of lead were discovered.
Zamfara State had recently employed a Chinese company to mine gold in the area, adds our correspondent.
But villagers had also attempted to capitalise by digging for the precious metal themselves - an illegal activity in Nigeria.