The civilians were reportedly ambushed and killed brutally.
The United Nations has condemned the killing of more than 30 civilians by terrorists suspected to be members of the Islamic State of West Africa (ISWAP) in Gamboru Ngala Local Government of Borno.
The civilians were primarily fishermen.
Other civilians who were said to have also suffered various degrees of injuries are now being taken care of in health facilities.
The United Nations resident and humanitarian coordinator in Nigeria, Matthias Schmale, made the condemnation in an official statement released Thursday evening in Abuja.
He expressed sadness over the incident that happened in Mukdolo village, a border community.
Mr Schmale said several civilians were still missing following the deadly attack.
"The victims of this heinous attack were fishermen and farmers eking out a livelihood in a very insecure environment. They included both internally displaced persons (IDPs) and host community members from the neighbouring Dikwa Local Government Area," he said.
The UN official said the attack has shown the real threat that internally displaced persons and other people face in the region.
He called on all parties involved in the conflict to adhere to the obligations of international human rights.
Mr Schmale also called on government officials to investigate the act of terrorism.
"This deeply shocking attack is another horrific reminder of the real threats of violence and insecurity that IDPs and other people affected by more than 13 years of the non-international armed conflict in the region continue to face daily in their struggle to survive.
"The village of Mukdolo had been abandoned prior to the attack due to the activities of non-state armed groups.
"I remind all parties to the conflict to adhere to their obligations under international humanitarian and human rights law to protect civilians from harm.
"I also call on State authorities to speedily investigate this crime and swiftly bring the perpetrators to justice," he said.
Borno is the centre of a 13-year-old Boko Haram insurgency that has led to the death and displacement of millions of people since at least 2010. The ISWAP has also joined the list of threats in the region fighting for supremacy between itself and members of the Boko Haram group.
