By Tiemoko Diallo
BAMAKO (Reuters) -The death toll from last week's accident at an artisanal gold mine in southwest Mali has risen to more than 70, the head of Mali's Mines Chamber said on state radio on Thursday.
The deaths were caused after a shaft collapsed on Friday inside an artisanal gold mining site in the Kangaba Cercle in Mali's southwestern Koulikoro Region.
The mines ministry reported over 40 killed on Wednesday but said that figure was provisional.
The President of Mali's Mines Chamber, Abdoulaye Pona, who headed a government delegation dispatched to the area on Thursday, told state radio the death toll had risen to over 70, including one woman.
He said the authorities would investigate the incident.
Mines ministry spokesperson Baye Coulibaly told Reuters the informal miners were digging at a site for which Toubani Resources has an exploration permit.
Earlier on Thursday, Toubani said the accident had occurred in an isolated area of its Kobada gold project concession, where it had not previously conducted any drilling.
Its business operations are unaffected, it said in a statement.
Artisanal mining is a common activity across much of West Africa and has risen in recent years due to growing demand for metals and rising prices.
Deadly accidents are frequent as the artisanal miners often use unregulated digging methods.
(Writing by Sofia Christensen and Alessandra Prentice;Editing by Alison Williams, Mark Potter and Aurora Ellis)