The regional force deployed in the east of the Democratic Republic of Congo announced on Monday that it was sending a "verification mission" to the area where the M23 rebels allegedly killed 11 men at the weekend.
Local sources told news agency AFP that the massacre had occurred in Rutshuru territory, some 100 km north of Goma, capital of North Kivu province.
According to the same sources, the bodies were discovered after the withdrawal from the area of M23 rebels, who allegedly clashed with other armed groups there.
Reacting to the allegations, political spokesman for the M23 rebels, Lawrence Kanyuka, denied any involvement in the massacre and added that the M23 had already handed over the territory to the East Africa Community regional force.
There has been a fragile truce between the M23 and the regular Congolese forces since the EAC force was deployed in the region a few months ago. But sporadic clashes pit the rebels against armed groups claiming to be patriots.