GOMA, DR Congo, Dec. 8 -- At least 14 peacekeepers were killed on Thursday night in an attack by suspected ADF rebels in the eastern part of the Democratic Republic of Congo (DRC), the United Nations mission in the DRC said Friday.

Five DRC soldiers were also killed and 53 other peacekeepers wounded in the attack in North Kivu province, the United Nations Organization Stabilization Mission in the DRC (MONUSCO) said in a statement.

"Suspected ADF elements conducted an attack against a MONUSCO Company Operating Base at Force at Semuliki in Beni territory, North Kivu. This resulted in protracted fighting between suspected ADF elements and MONUSCO and FARDC Forces," the statement said, referring to the armed forces of the DRC.

"Initial reports indicate that 14 MONUSCO peacekeepers and five FARDC soldiers were killed. An additional 53 MONUSCO peacekeepers were wounded in this incident.

At the United Nations, UN Secretary-General Antonio Guterres "unequivocally" condemned the "worst attack" on UN peacekeepers in recent history.

"These deliberate attacks against UN peacekeepers are unacceptable and constitute a war crime," Guterres said.

Maman Sidikou, Guterres' special representative in the DRC and head of MONUSCO, also condemned "in the strongest terms" the deadly attack.

"Attacks against those who are working in the service of peace and stability in the Democratic Republic of the Congo are cowardly and constitute serious violations," Sidikou was quoted as saying in the MONUSCO statement.

"I wish to convey my sincere condolences to the families and loved ones of peacekeepers and FARDC soldiers who lost their lives, or were injured in the service of peace in the Democratic Republic of the Congo in the last hours," he said.

"MONUSCO will take all actions to ensure that the perpetrators are held accountable and brought to justice," Sidikou said.

GOMA, DR Congo, Dec. 8 -- At least 14 peacekeepers were killed on Thursday night in an attack by suspected ADF rebels in the eastern part of the Democratic Republic of Congo (DRC), the United Nations mission in the DRC said Friday.

Five DRC soldiers were also killed and 53 other peacekeepers wounded in the attack in North Kivu province, the United Nations Organization Stabilization Mission in the DRC (MONUSCO) said in a statement.

"Suspected ADF elements conducted an attack against a MONUSCO Company Operating Base at Force at Semuliki in Beni territory, North Kivu. This resulted in protracted fighting between suspected ADF elements and MONUSCO and FARDC Forces," the statement said, referring to the armed forces of the DRC.

"Initial reports indicate that 14 MONUSCO peacekeepers and five FARDC soldiers were killed. An additional 53 MONUSCO peacekeepers were wounded in this incident.

At the United Nations, UN Secretary-General Antonio Guterres "unequivocally" condemned the "worst attack" on UN peacekeepers in recent history.

"These deliberate attacks against UN peacekeepers are unacceptable and constitute a war crime," Guterres said.

Maman Sidikou, Guterres' special representative in the DRC and head of MONUSCO, also condemned "in the strongest terms" the deadly attack.

"Attacks against those who are working in the service of peace and stability in the Democratic Republic of the Congo are cowardly and constitute serious violations," Sidikou was quoted as saying in the MONUSCO statement.

"I wish to convey my sincere condolences to the families and loved ones of peacekeepers and FARDC soldiers who lost their lives, or were injured in the service of peace in the Democratic Republic of the Congo in the last hours," he said.

"MONUSCO will take all actions to ensure that the perpetrators are held accountable and brought to justice," Sidikou said.