Flamengo president says it is ‘the worst tragedy to happen to the club in its 123 years’

Rio de Janeiro has declared three days of mourning as investigators seek to determine the cause of the fire that killed 10 teenage footballers at the training centre of the city’s Flamengo football club on Friday morning.

Cláudio Castro, the vice governor of Rio de Janeiro state, said authorities were looking at the possibility of a short circuit in an air conditioning unit.