Tutsi

The fighters are led by ethnic Tutsis who say they took up arms to protect the rights of the minority group - and because the Congolese authorities reneged on an earlier peace deal.

They claim they are revolutionaries battling a failed state, and defending the rights of minority Tutsis.

The countries share a similar language and ethnic make-up - with Tutsi and Hutu communities often vying for power - and both have suffered terrible ethnic-based massacres.

The M23 says it is fighting to achieve better rights for the Tutsis, an ethnic minority group in DR Congo, and to bring order to a failed state.

Central to their campaign is the assertion that ethnic Tutsis living in DR Congo are being persecuted.