The boy, a class I student, suddenly collapsed in the second-floor corridor of Pawar Public school in Powai at around 10 this morning when he and some other boys were playing during the recess, police said.
He was rushed to a hospital where he was declared 'brought dead', said senior inspector A Dharmadhikari of Sakinaka police.
According to his parents, the boy wasn't suffering from any disease.
The cause of death will be known after autopsy report becomes available, the officer added.
Police went through CCTV footage of the spot and spoke to the school staff, said another police official.
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