As the fire engulfed the Flamengo's youth team's training ground 10 young footballers lost their lives.
Three more people were injured as the fire broke out at Ninho de Urubu, the training ground of Flamengo which is Brazil's one of the biggest and well-known clubs.
The fire broke out when players were sleeping. However, the reason behind the mishappening is yet to be known. According to local media reports, the fire began at 05:10 (07:10 GMT) and was extinguished by 07:30.
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Victims are yet to be identified. However, victims age ranged from 14 to 17. They were sleeping at the club's dormitory.
The injured were taken to nearby hospital, firefighters say.
The Ninho de Urubu centre was renovated two months ago.