The local government in the nearby city of Yulin told CNN on Tuesday that 106 had been injured and the search for survivors continued.
It added that initial investigations showed some kind of explosive had caused the blast.
According to state news agency Xinhua, the blast took place at about 2 p.m in a prefabricated house which had been built inside a larger residential compound.
Rescue crews were combing through the rubble overnight in the hope of finding survivors and to discover the cause of the explosion.
