Officials have said the three-story residential building had been marked for demolition and that the school was operating illegally on the top two floors. It is still not clear how many people were inside when it collapsed.
Rescue crews halted their search on Thursday, saying they had reached the building's foundation without finding any other victims. Some anguished families protested and sifted through the rubble for any sign of their children.
Building collapses are all too common in the West African nation, where new construction often goes up without regulatory oversight. Official moved through the neighborhood on Thursday, marking other derelict buildings for demolition.
Adeyemo Sunday, the father of twins, mourned one of his sons. The other was pulled out alive, he said. Sunday said his family lived on the building's second floor and he sent his boys to school there so they wouldn't have to travel far.
Another parent, Yewande Ogunsanwo, said her son remained in critical condition on Thursday. "Let's thank God for God, he's getting better but his condition is so critical," she said. "The pain is too much."
The collapse came as President Muhammadu Buhari, newly elected to a second term, tries to improve the distressed infrastructure in Africa's most populous nation.
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