The group was also allegedly ambushing people at night, assaulting them and robbing their valuables.
They were arrested on Thursday, September 16, in operations conducted in Kazirabonde and Gishyeshye cells of Rukoma Sector.
Police also seized from the group six bags of unprocessed minerals.
The Southern region Police spokesperson, Superintendent of Police (SP) Theobald Kanamugire said that the suspects were arrested in partnership with local leaders following separate complaints from residents.
“Local residents in Kazirabonde and Gishyeshye cells have been reporting groups of people armed with machetes, who ambush them at night and rob them of their valuables," said SP Kanamugire.
"With the help of local authorities and residents, we compiled a list of suspects, all who belong to an illegal mining racket that calls itself Abahebyi. This facilitated the successful operation in which the 12 suspects were arrested. They were found in possession with six sacks of unprocessed minerals and traditional tools their were using in mining and ambushing people," he added.
There have also been complaints from the management of mineral concessions where the groups were illegally operating. The group include those who were either dealing in drugs of abusing drugs.
All the suspects were handed over to RIB at Rukoma station for further investigation.
Article 54 of the law N° 58/2018 of 13/08/2018 on mining and quarry operations, states that; any person, who undertakes mineral or quarry exploration, exploitation, processing or trading without a licence, commits an offence.
Upon conviction, the offender is liable to imprisonment for a term of between two and six months and a fine of not less than Frw1 million and not more than Frw5 million or only one of these penalties.
The court also orders confiscation of any seized minerals or quarry in storage, trading or processing without a license.
Article 166 of law determining offences and penalties in general states that, any person convicted of theft is liable to imprisonment for a term of not less than one (1) year and not more than two (2) years and a fine of not less than Rwf1 million and not more than Rwf2 million, a community service in a period of six (6) months or only one of these penalties.
In article 167, however, the penalty for theft doubles if the act was carried out at night or by more than one person.