The incident took place yesterday around 1 pm when six people entered the mining quarry searching for a colleague whom they suspected went missing inside.
Four of them died immediately of asphyxia while two others survived and narrated the ordeal.
The four bodies have been retrieved from the mining site but it has not yet been established whether the colleague was inside the quarry.
Police spokesperson in Western Province, CIP Emmanuel Kayigi has cautioned residents against illegal mining.
“The incident took place in a Wolfram mining site which the district had closed. Six people entered to search for a missing colleague and experienced oxygen deprivation. Four died while two others who survived are admitted at Kabaya Hospital,” he said.
Recently, another mining site in the Mwulire sector, Rwamagana district collapsed and killed 14 people including 7 men and 7 women.