The United Nations said on Wednesday two Tanzanian army officers serving as UN peacekeepers were killed and 13 others were injured after they were attacked by rebels in the Democratic Republic of the Congo (DR Congo).

The UN said in a statement issued in the commercial capital Dar es Salaam that four other peacekeepers were reported missing.

The deaths of the two army officers bring to five the number of Tanzanian peacekeepers who have been killed in the DR Congo in the past two years.

The statement said the army officers were killed when a UN Organization Stabilization Mission in the Democratic Republic of the Congo (MONUSCO) convoy was ambushed and came under fire from suspected Allied Democratic Forces (ADF) elements in Beni territory at North Kivu.

“The attack occurred as MONUSCO was carrying out its protection of civilians mandate,” it said, adding that the attack followed an incident on May 4 when a MONUSCO helicopter carrying the force commander was hit by gunfire from unidentified armed elements in the same area.

Joseph Masanja, a spokesman for the Tanzania People’s Defense Forces (TPDF), confirmed the killings, saying the army was making arrangements to inform the victims’ next of kin and logistics of bringing their bodies back to Tanzania.

UN Secretary-General Ban Ki-moon strongly condemned the killing of the two Tanzanian peacekeepers, said the statement.

“The Secretary-General also condemns in the strongest terms the continuing atrocities perpetrated by the ADF against defenseless civilians in the Beni area,” it said.

Ban offered his sincere condolences and sympathy to the bereaved families and the government of Tanzania, it said.

The statement said the UN remained committed to taking all necessary actions in line with Security Council resolution 2211 (2015) to protect civilians and neutralize armed groups in eastern DR Congo.

In July, seven Tanzanian soldiers who were part of the UN- Africa Mission in Darfur (UNAMID) were killed after gunmen ambushed their convoy.

Their 17 colleagues were seriously wounded in the incident which was described as the deadliest single attack ever on the international force in Sudan.