Local administrator Amisi Kalonda said the violence took place overnight about 20 kilometers from the town of Beni.
Military spokesman Capt Mak Hazukay Mongba said there was an operation in the area as part of efforts to neutralise the rebel group but he declined to give a death toll.
Human Rights Watch says that ADF rebels have killed about 1,000 people in the Beni region over the last three years. The Congolese army has captured dozens of rebels including a dozen who were sentenced to death.