A small artisanal gold mine collapsed in northern Angola at the weekend, claiming the lives of at least 28 miners, nearly half from one family, reports and officials said.

Angola’s rich deposits of diamonds and other minerals, including gold, reportedly draw thousands of men, including from neighbouring countries such as the Democratic Republic of Congo, to illegal and uncontrolled mines.

Authorities recovered the bodies of 28 people aged between 18 and 45 years following the collapse early on Saturday at the mine in Bengo province, northeast of the capital, Luanda, a police official told national broadcaster TPA.

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“These young people were extracting strategic minerals, namely gold, in this area and at a certain point, the mine collapsed,” he said on Sunday, adding that authorities were searching for other bodies.

A rescue department official gave the same death toll to local media and said that 13 of the dead were from the same family.

Bengo officials estimated there were around 7,000 illegal miners involved in gold extraction in the province, the Angola Press Agency reported.