The Red Cross says 115 bodies have been found in the Central African Republic's town of Bangassou following several days of attacks by militants.
"We found 115 bodies and 34 have been buried," said Antoine Mbao Bogo, the president of the aid group's local branch, from the capital Bangui on Wednesday.
"They died in various ways: from knives, from clubs and bullet wounds."
The figure is more than four times the toll previously reported. A top UN official had previously said only 26 civilians were killed.
Bangassou, a diamond-mining town in the Central African Republic, has witnessed an escalation in fighting over its control since 2013. In March the same year, the country fell into chaos when then President Francois Bozize was ousted by the mainly Seleka rebel alliance and was replaced by Michel Am-Nondokro Djotodia, the first Muslim to hold the presidency in the generally-Christian nation.
The replacement, however, caused a series of deadly retaliatory attacks between the Seleka rebels and the Christian militia known as anti-balaka.
Some 13,000 peacekeepers have been deployed to the country by the United Nations as part of the UN peacekeeping mission in CAR (MINUSCA). Civilians say the mission has failed to protect them against armed groups.
Last week, hundreds of militia with heavy weaponry captured Bangassou and UN peacekeepers have been trying to regain control over the southeastern town ever since.
UN spokesman Herve Verhoosel said on Wednesday the peacekeepers seized back key points thanks to the deployment of additional UN troops and air raids.