U.N. High Commissioner for Human Rights Michelle Bachelet is calling for urgent measures to protect civilians who are at the mercy of marauding armed groups in Mozambique's northern Cabo Delgado province.
According to media reports, dozens of people were beheaded by Islamist militants in northern Mozambique earlier this month.
The escalating violence in Cabo Delgado province has sent thousands of people fleeing by land and by sea to escape what is thought to be an increasingly dangerous and chaotic situation.
Thousands of others reportedly remain trapped in conflict areas, with many forced to hide in the bush for days.
Bachelet's spokesman, Rupert Colville, said Friday that people trapped in areas of conflict, as well as many of those displaced across the province, have barely any means of surviving. He said some areas have been without humanitarian aid for more than six months.
"Those who remain have been left deprived of basic necessities and are at risk of being killed, sexually assaulted, abused, kidnapped, or forcibly recruited by armed groups. And, those that flee may die in the process."
The high commissioner is appealing to Mozambican authorities to protect the civilians at risk and to ensure humanitarian agencies can deliver life-saving assistance to them.
Spokesman Colville said there has been a string of gruesome attacks in several villages over the past two weeks. He said witnesses report homes and public facilities have been burned and dozens of people killed.
"There also have been reports of human rights violations committed by Mozambican security forces in recent years, including extrajudicial killings, ill-treatment, use of force violations, arbitrary detentions, including of journalists, and unlawful restrictions on the freedom of movement," Colville said.
High Commissioner Bachelet said all parties to the conflict must strictly adhere to their obligations under international law and make sure any forces under their control do so as well.
She said her office is available to support the government in its efforts to carry out the obligations and to help the people of Mozambique in any way it can.