Rescuers in Burkina Faso have found the bodies of four of the eight miners who have been missing since their shaft flooded in mid-April, the government said on Wednesday.

The accident happened on April 16 at a zinc mine owned by Canada’s Trevali Mining in Perkoa, around 100 kilometres (60 miles) west of the capital Ouagadougou. Six Burkinabe, a Zambian and a Tanzanian went missing in the shafts 700 metres (2,300 feet) underground.

“Unfortunately, after 39 days of intense searches, the lifeless bodies of four miners have been found,” government spokesman Lionel Bilgo said in a statement.

The search was continuing for the four miners who remain missing, he said. The statement did not specify the nationalities of those whose bodies were found.

Rescue teams have for weeks been pumping out water from the mine, with extra support and equipment being brought from Ghana. It was hoped that the missing miners had been able to make it to the mine’s ‘refuge chamber’ 580 metres underground, which was equipped survival kits including water, food and medicine.