Around 100 miners are estimated to have died inside a collapsed gold mine in Sudan's Darfur region and nine rescuers trying to free them are now trapped, a miner said on Friday.
"Nine of the rescue team disappeared when the land collapsed around them yesterday (Thursday)," said the miner, who had visited the scene and asked to remain anonymous.
On Monday the unlicensed desert gold mine began to collapse in Jebel Amir district, more than 200 kilometres (125 miles) northwest of the North Darfur state capital El Fasher.
The stench of death is now seeping out of the baked earth, the miner said.
"Yesterday eight bodies have been found and still they are looking for the others," he said.
"According to a count by people working in the mine, the number of people inside is more than 100."
On Thursday the Jebel Amir district chief, Haroun al-Hassan, said "the number of people who died is more than 60", but it was unclear whether anyone might still be alive.
He said rescuers were using hand tools out of fear that machinery would cause a further collapse.
But the ground fell around some of the rescuers anyway.
"We are still searching for the bodies," the district chief said on Saturday, adding it was unclear how many victims there might be. "We are having difficulty to reach them."
Production from unofficial gold mines has become a key revenue source for the cash-strapped government in Khartoum.
It is also a tempting but dangerous occupation for residents of Sudan's poverty-stricken western region of Darfur which has been devastated by a decade of civil war.
A humanitarian source said earlier this year that close to 70,000 people were digging for gold in Jebel Amir.
Sudan is trying to boost exports of the precious metal and other non-petroleum products after the separation of South Sudan two years ago left Khartoum without three-quarters of its crude oil production.
The lost oil accounted for most of Khartoum's export earnings and half of its fiscal revenues, sending inflation above 40 percent while the currency plunged in value on the black market.
Sudan's Mining Minister Kamal Abdel Latif said traditional mining produced 41 tonnes of gold worth $2.5 billion (1.9 billion euros) from January to November last year.
In 2011, the government estimated there were more than 200,000 unlicensed artisanal gold producers, generating most of the country's output of the resource.
Sudan's central bank has entered the market, trying to buy from the small producers.
Seven weeks of clashes over gold between two Arab tribes in Jebel Amir early this year killed more than 500 members of the Beni Hussein tribe, an MP for the group has said.
The violence uprooted an estimated 100,000 people.
The fighting between the Beni Hussein and Rezeigat erupted when a leader of the latter tribe who is a border guard officer apparently laid claim to a gold-rich area inside Beni Hussein territory, Amnesty International said.
Beni Hussein refused to pay newly imposed government mining fees which amounted to "huge, huge money", the rights watchdog said.
In Darfur's latest tribal violence, at least 80 people were killed in fighting between Arab groups in southwestern Darfur, leaders said on Friday.
"Fighting was going on until last night and from our side we have 37 dead," said Ibrahim al-Sheikh, a leader of the Beni Halba tribe.
A Gimir chief, Abaker al-Toum, said 44 of his people had died.
They clashed in Edd al-Fursan, about 100 kilometres southwest of the South Darfur state capital Nyala.
Both sides agreed they were battling over land, with each side claiming ownership.
Competition for resources, from water to gold, is a key driver of conflict in Darfur, where ethnic rebels rose up against the Arab-dominated Khartoum government in 2003.
While the worst of the violence has long passed, rebel-government battles continue along with tribal disputes, inter-Arab fighting, kidnappings, carjackings and other crimes.