Congolese naval forces in the area blame the Ugandan navy.
DR Congo's navy on Wednesday accused Ugandan troops of killing four Congolese fishermen, whose bound and bullet-riddled bodies surfaced on Lake Edward, which is shared by the two neighbouring countries.
It is latest sign of escalating tensions between Democratic Republic of Congo and Uganda over the lake, the smallest of eastern Africa's Great Lakes, where the two sides engaged in deadly clashes earlier this year.
"The fishermen had been on the lake since Friday and had not returned. Yesterday (Tuesday) we saw their burnt and tied up bodies floating in the lake," said Jonas Kataliko, head of the fishermen's association in the lakeside village of Kyavinyonge.
Major Jean Tsongo, who heads Congolese naval forces in the area, blamed
"It was Ugandan soldiers who killed these Congolese fisherman," he said. "They burned their canoes and the bodies arrived here tied up, burnt and with bullet holes."
There was no immediate comment from the Ugandan navy.
Strains between the two countries, who disagree over the sharing of energy resources, worsened in July, when 16 Congolese fishermen, four Ugandan military personnel and three civilians were killed in clashes between the Ugandan navy and DRC forces.