Mount Nyiragongo turned the sky red and spewed out a river of lava on Saturday, but stopped short of Goma, a city of two million just south of the volcano.
At least 15 deaths have been confirmed, but the number is likely to rise as officials reach the hardest-hit areas.
Nine of the victims died in a traffic accident as people fled.
Four others were killed as they tried to escape a prison while two were burned to death, government spokesman Patrick Muyaya said on Sunday.
