Rescuers are digging through rubble after a gold mine collapsed in the Democratic Republic of Congo, leaving about 50 people feared dead.
Bundya blamed "soil subsidence caused by torrential rain" for the accident.
"The main problem is that people did not heed the rain", he said outside his office in the mining town in Congo's mountainous and mineral-rich South Kivu province.
"The miners and the stone carriers were swallowed up by the waters", said the mayor of nearby town Kamituga, Alexandre Bundya.
Meanwhile, no bodies had been recovered so far, but rescues officials are the scene of the incident.
DRC's mineral-rich but volatile east faces regular attacks from a plethora of militias and rebel groups which operate freely in the region.
"Several miners were in the well which was buried and no one was able to get out".
An eyewitness told AFP that heavy rains meant that "water went into the three tunnels".
Accidents of this kind are not uncommon in the unregulated artisanal mines in Congo.
The cause of the landslide is now under investigation.
'The authorities must take responsibility instead of taxing these miners.
Deadly collapses occurred earlier this year in Maniema and in Katanga, killing at least 18 people.
Because many such mines are in remote areas however, the accidents are under-reported.
The mine was not located on the Kamituga gold concession owned by Canadian miner Banro Corporation, the company's chief executive said.
Thousands of informal miners operate in and around mines in DRC, which produces more than half of the world's cobalt, a key component in electric vehicle batteries. The World Bank said in 2018 that 72 percent of the population lived on less than 1.9 dollars a day.