A fire tore through the sprawling training complex of one of Brazil's biggest soccer clubs, killing 10 people and leaving three injured teenagers in Rio de Janeiro, firefighters said.

Brazilian firefighters were called in just after 5 a.m. Friday to battle a blaze at the Ninho de Urubu training ground of the Flamengo soccer club in the city's western region, a fire official told The Associated Press.

There was no word yet on the cause of the fire.

The ages and identities of those killed were not released but the three injured were 14, 15 and 16 years old, the fire official said. The injured were taken to local hospitals and their conditions were not immediately known, said the official, who asked his name not be used due to his agency's rules.

Local media reported that the fire started in a dorm where youth soccer players sleep. The fire official said that could not be confirmed.

Aerial images from Globo TV showed smoke emerging from a charred area.

Like many professional clubs in soccer-crazed Brazil, Flamengo has a youth development program for promising young players in their early teens. Many players stay at the facilities while training.

Messages to Flamengo officials were not immediately answered.