At least 43 illegal miners died when part of a copper mine collapsed in southeastern DR Congo, a Congolese official said on Friday.
Details of the exact toll were still unclear after two galleries caved on Thursday in at a mine in the Kolwezi area operated by Kamoto Copper Company (KCC), a subsidiary of the Swiss company Glencore.
Glencore had put the number of fatalities at 19 but noted in a statement that there could be "possible further unconfirmed fatalities".
Richard Muyej, governor of the Lualaba province, on Friday told a press conference that 43 miners had died in the accident. A day earlier he had put the toll at 36.
But the Red Cross and some civil groups put the number of fatalities even higher, at between 60 and 80 dead.
Muyej was quoted as saying Friday: "After the burials we will hold a big meeting with leaders of the illegal miners to agree once and for all on the rules."
The region is rich in copper and cobalt.
Glencore had said KCC had observed a "growing presence" of illegal miners, with on average 2,000 people a day intruding on its operating sites.
Illegal mining is common and frequently deadly in Democratic Republic of Congo, where safety is often poor and risk-taking high.
Figures indicating the scale of the problem are sketchy, given that many mines are illegal and work in remote areas.