Dozens of people have been killed in a gold mine collapse in Sudan's Darfur region, said the chief of the district where fighting over gold in January led to the region's worst unrest in years. "The number of people who died is more than 60," Haroun al-Hassan, the local commissioner in Jebel Amir, North Darfur, said on Thursday. He added that rescue operations were still taking place after Monday's accident. "I cannot give exact figures because no one got precise numbers of how many people were going inside the tunnel," which went down 40 metres (yards), he said. Rescuers were using traditional tools to try to reach the victims, he said, without specifying whether anyone might still be alive. "We cannot use machines because if they came near, the ground will collapse. People are using traditional tools and because of this, the rescue is very slow," Hassan said.