KINSHASA: Democratic Republic of Congo’s President Felix Tshisekedi said Wednesday his military was undertaking a “vigorous” response as Rwanda-backed fighters captured new territory in the east, and warned of possible regional “escalation”.

The M23 fighters were advancing on a second front Wednesday, local sources told AFP, seizing two districts in South Kivu after mostly routing the Congolese army from North Kivu’s provincial capital.

“A vigorous and coordinated response against these terrorists and their sponsors is underway,“ Tshisekedi said in an address to the nation, after lamenting the “unprecedented worsening of the security situation”.

He also condemned the “inaction” of the international community in the face of intensifying conflict in DRC’s east.

“Your silence and inaction... are an affront” to the DRC, he said in the televised address, adding that the advance of Rwanda-backed fighters could lead “straight to an escalation” in the region.

The weeks-long march of the M23 armed group has prompted calls for crisis talks, as well as rising international criticism and warnings of a looming humanitarian crisis.