Eleven ruby miners have died in northern Mozambique over three days at an illegally dug mine.

Obete Matine, the general inspector at the Ministry of Mineral Resources and Energy, said the walls of one tunnel had first collapsed on Tuesday in Cabo Delgado province’s Montepuez district, killing one man.

But instead of abandoning their search for rubies the other miners went on digging, he said.

On Tuesday night, there was a second collapse and two more people died.

Even that did not bring the mining operation to a halt as on the nights of Wednesday and Thursday, there were a further eight deaths.

The inspector noted that most of the victims were young people used by gangs of smugglers to extract rubies and other precious stones from the mineral-rich region.

He said illegal mining happened mostly during the rainy season when it was easier to extract the stones from the ground, but much more dangerous.

The illegal mine had been dug in an area allocated to Montepuez Ruby Mining, a company which is 75% owned by UK firm Gemfields