Contaminated water from a gold mine in Ivory Coast that leaked into a river from a cracked valve "slightly poisoned" 185 people, officials said Tuesday.
The Cavally River, an important resource for drinking water and fish for the region's inhabitants, runs for several hundred kilometres (miles) along the west of the country.
Local official Moussa Dao told AFP that at the end of June, "a rupture in one of the mine's pipes" allowed "some of the water to flow" into the river.
"The alert was given directly to the local population by Endeavour Mining," said Dao, adding that "dead fish were found the next day".
Dao said that 185 people were "slightly poisoned" and were reporting "bloating and vomiting" at the Ouyatouo village health centre where they were treated.
No new cases of poisoning have since been reported, he said.
The country's environment ministry confirmed Tuesday that the accident resulted from a "broken valve" in a pipe carrying cyanide-laced mud from the extraction process at the mine, which spilled into a nearby river that eventually flowed into the Cavally.
It said the pollution had caused "vomiting and headaches" for residents as well as "massive deaths of fish".
According to the local chief, Celestin Balla, every day since the incident people who had consumed the water and fish "have been showing signs of diarrhoea, headaches and aches".
In a statement sent to AFP on Tuesday, Endeavour Mining "categorically rejects the allegations of massive pollution of the Cavally River and of endangering local populations".
The group does, however, acknowledge an incident involving a "faulty valve... resulting in a leak of around three cubic metres of sludge and decantation water into the site's diversion channel", "a small part of which could have been discharged into the Cavally River".
In a statement on Sunday, it acknowledged that the liquid had reached the river.
But Endeavour said it had replaced the faulty valves and "monitored and tested" the water in the river to ensure there was "no contamination".
Dao said he had taken a number of measures, including banning the consumption of fish and drinking water from the river, and the provision of drinking water to residents.
The Ivorian anti-pollution centre went to the site to take samples and is due to report its findings in the next few days.