Rwanda Investigation Bureau (RIB) on April 13, paraded 12 people suspected of illegal importation and possession of firearms, armed robbery, formation of a criminal gang and being part of it.
They are also being accused of murder and usurpation of titles and wearing a uniform with an intention to mislead the public.
The suspects include one woman who, according to RIB, is among others charged with accomplice in the committed crimes.
She is accused of using her dowry to buy a gun that her father, Lambert Biyoga, used to commit the alleged offences.
Biyoga and another suspect called Fidel Bavugamenshi were arrested during primary investigations and led to the arrest of the 12 co-accused.
According to RIB, the group is composed of some individuals who have been dismissed from the Rwanda Defence Force (RDF) because of misconducts. They also include ex-prisoners.
The investigation bureau said that the alleged crimes were committed on different instances; in December last year, February and March this year in Nkombo, Gihundwe and Kamembe sectors in Rusizi district.
"They would allegedly commit the unlawful acts clad in military outfits with arms, calling themselves security officials so as to take advantage of the public," RIB said in a tweet.
Last year, reads a statement by RIB, some of the group members shot and killed one lady and stole from her Rwf470, 000.
In total, over three million Rwandan Francs were stolen from Rusizi district residents, and one person succumbed to these activities.
"RIB consoles those affected by these acts, including those who lost their loved ones. We will never tolerate anyone who destabilizes the security of citizens, therefore, those planning to do so should quit it because they will not run away from justice."
According to investigators, the suspects were arrested in collaboration with citizens and security personnel.
The suspects are currently detained at Kamembe RIB station.