Seven suspected illegal miners were confirmed dead and more than 20 others were missing and presumed dead after heavy rains caused landslides that buried them inside tunnels they had been digging at a copper mine in Zambia, police and local authorities said Saturday.

No bodies had yet been retrieved after the landslides late on Thursday night (Nov. 30), police said. Many of the victims were believed to have drowned.

The miners were digging for copper ore at the Seseli open-pit mine in the copper-belt city of Chingola, around 400 kilometers (250 miles) north of the capital, Lusaka, according to police. The landslides happened some time between 9 p.m. and 10 p.m. on Thursday, police said.

Police gave names or partial names of seven confirmed victims and said all of the miners in the tunnels are 鈥渟uspected to have died.鈥� Police didn鈥檛 say how many miners in total there were in the tunnels but Chingola District Commissioner Raphael Chumupi told The Associated Press that there were at least 36.

Government officials said that more than 30 miners were trapped in the tunnels but couldn鈥檛 give an exact number.

The victims were buried at multiple sites, police said. Police, a mine rescue team and emergency services were at the mine.

鈥淭he bodies are not yet retrieved as efforts are being made to retrieve them,鈥� police spokesperson Rae Hamoonga said.

Chumupi said the miners were engaged in illegal mining without the knowledge of the mine owners. He said they were buried in three separate tunnels.

Illegal artisanal mining is common in Chingola, where the open pits are surrounded by huge waste dumps made up of rock and earth that has been dug out of the mines.

Zambia, a southern African nation of 20 million people, is among the 10 biggest copper producers in the world.

Tsvangirayi Mukwazhi, The Associated Press

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