The tanker overturned on a highway through the village and as residents crowded around the vehicle spilled fuel ignited and fire rapidly engulfed nearby homes and a local cinema hall.
Some of the villagers had gathered around the vehicle to siphon off fuel from the wreckage.
Among the dead were 61 children and 36 women, the office of the International Committee of the Red Cross (ICRC) in South-Kivu province said.
Marcellin Cishambo, the governor of South-Kivu province, said that more than 100 people remained in hospital on Monday. A similar number had been able to leave after being treated for their injuries.
Thirty-two people suffering serious burns were taken to hospital in Bukavu, the regional capital, and Uvira.
The UN-backed Okapi radio station reported that Uvira hospital was short of medicines and that the wounded had been forced to buy supplies themselves from pharmacies in the town.
"People are suffering terribly," Namweze Bahizire, a nurse at the hospital, told The Associated Press news agency.
"Yesterday we lost two men and a woman a few hours after surgery and during the night we lost another male victim."
In Sange, Red Cross workers sprayed chlorine and poured disinfectant powder over the blackened scene of the explosions as priests prayed during a brief memorial service on a football field.
"It's a miserable, poor life we have here in Congo," Muke Ndengwa, whose 15-year-old son was hospitalised after the blast, said.
"When we had the war here, we had everything stolen from us. Now we have lost so much again."
Most of the dead were buried in two mass graves outside the village.
"We have decided to make mass graves because most of the bodies are completely burnt and are not identifiable, and also to prevent the corpses from decomposing" Jean-Claude Kibala Nkolde, the deputy provincial governor, told Radio Okapi.