"More than 61,000 children have fled a new wave of violence" in the Cabo Delgado province in the last two months, "the highest number uprooted in such a short period," the children's charity said in a statement.
Fresh unrest broke out in the lawless province a few weeks ago, according to local reports and figures for displaced people from the UN migration agency IOM.
The UN migration agency IOM on Monday placed the total number of displaced people at 112,894 from December 22 to March 3.
The thousands of families have fled by bus, canoe or on foot.
A Doctor's Without Borders (MSF) psychologist, Esperanca Chinhanja, based in one of the districts of Cabo Delgado cautioned about the mental impact of the recent attacks.
FILE —Displaced people from the province of Cabo Delgado walk through the streets of Namapa, Erati district of Nampula, Mozambique on February 27, 2024.
"Some people experience anxiety, panic attacks, insomnia, isolation and have recurrent thoughts. Some share they lost the meaning of life and mention suicide thoughts," Chinhanja said.
MSF said it was providing individual consultations for psychological support despite limited health infrastructure.
The insurgency erupted in October 2017 when fighters — since proclaimed to be affiliated the Islamic State group — attacked coastal areas in gas-rich northern Cabo Delgado, close to the Tanzanian border.
"There are repeated reports of beheadings and abductions, including multiple child victims," Save the Children said, adding that the conflict has "no immediate end in sight."
Forces from Rwanda and countries of the Southern African Development Community (SADC), deployed to Mozambique in July 2021 after years of jihadist attacks.