OUAGADOUGOU, Burkina Faso —  Heavy rains caused a mudslide at an illegal gold mine in Burkina Faso that killed at least 31 people, state-run radio said.

Miners dug through the mud to try to rescue survivors and pull out bodies in the mining village of Boussoukoula in southwest Burkina Faso, state radio said.

The accident comes after a June government order for unofficial mines to close until Sept. 30 because of the risk of accidents during the rainy season, when hastily dug tunnels can easily collapse.

The government estimates at least 200,000 miners work at unregulated gold mines in Burkina Faso, risking their lives by descending down deep mine shafts for gold to eke out a meager living.

Unlike large industrial mines, they are not registered with authorities and because there are thousands of such mines in West Africa, officials do little to enforce safety regulations.

"They (miners) hide and go for mining by night. This is the problem with traditional mining," Seka Ki, the director general of mining at the Ministry of Mining and Energy, told The Associated Press.

"That is why we do not promote traditional mining."