Suspected Islamist militants killed 16 people and burned down houses late on Wednesday in a village in eastern Democratic Republic of Congo, a witness and a civil society leader said.

An army spokesman in the area said early on Thursday that a combat patrol unit had clashed with the rebels, but gave no further details.

“We were having a drink with friends and all of a sudden we heard gunshots. Our first instinct was to flee. This morning we found 16 bodies, the victims including my eldest son,” said Luc Kakule Messo, a resident of the village of Kalembo, about 40 kilometres (25 miles) east of the city of Beni.

Mumbere Meleki Mulala, coordinator of a local human rights network, confirmed the death toll and blamed the attack on the Allied Democratic Forces (ADF), a Ugandan armed group active in the region.

The ADF has operated in the dense forests near the Ugandan border for more than three decades and began killing civilians in large numbers in 2014. In late 2019 Congo’s army launched a large-scale operation against them, sparking a violent backlash.

“It is regrettable and it is frustrating because every day we are counting the dead,” said Mulala.

The government declared a state of siege in North Kivu and Ituri provinces in May that was meant to halt the bloodshed, but civilian security has continued to deteriorate since, according to the Kivu Security Tracker, a research group affiliated with New York-based Human Rights Watch.