A fire at the training centre of Rio de Janeiro football club Flamengo killed 10 people and injured at least three others on Friday, firefighters said.
The fire broke out at Ninho do Urubu, a state-of-the-art training centre that was expanded and opened only two months ago. The facility has accommodation for teenage players.
"The kids from the Flamengo youth team were sleeping there at the time," lieutenant colonel of the fire brigade Douglas Henaut told Globo News.
Brazilian television channel Globo reported youth players were among the dead, after speaking to Henaut.
"We know the place, which is the accommodation, where the players in Flamengo's training base sleep. The identification of the victims will be done later by the Civil Police, in relation to the 10 people killed in the fire," he said.
"The possibility that the victims were sleeping exists, because of the timing and location of the fire. It is probable that they were asleep and weren't in the right condition to escape in time."
Henaut confirmed they do not yet know the cause of the fire. Firemen were called shortly after 5am local time.
Ariel footage showed corrugated iron roofs distorted by the fire and piles of charred items. Nearby trees were also scorched by the flames.
After years of financial difficulties, Flamengo last year spent 23m reais (£4.8m) to expand the Ninho do Urubu facilities.
In addition to accommodation for young players, the facilities include several pitches, an aquatic park, a gym, a medical centre and a mini stadium.
The Ninho do Urubu, or Vulture's Nest, is so called because the club's symbol is a vulture.
Vinicius Junior, the teenage Real Madrid forward who trained at the facility before joining the Spanish club last year, tweeted his condolences.
"What sad News! Praying for everyone! Strength, strength, strength," he wrote.
Flamengo are due to play close rivals Fluminense on Saturday in the semi-finals of the Taca Guanabara (Rio de Janeiro State Cup competition).
More to follow...