Five people have died after an illegal gold mine collapsed in southern Niger, a  mayor said Tuesday.

The accident occurred Monday in the Maradi region near the border with Nigeria, where 18 miners died late last year, Dan-Issa mayor Adamou Gueraou told AFP.

It happened in "one of the mines where all clandestine mining was banned in November after a fatal accident," he said.

Thousands of miners, many of them Nigerians, converged on the Garin-Liman district after gold was discovered there last August.

The authorities banned digging after the fatal collapse in November and placed the site under surveillance.

"Despite the closure and the security measures, the miners come back to dig, even at night," said Gueraou.

Illegal gold mining is a major activity in the impoverished landlocked state. Security precautions are often negligible and collapses frequent.

The country has only one industrial-scale legal mine, located at Samira in the western region of Tillaberi.