Testimonies from the residents describe how the area was transformed into a war zone, with corpses lying on the asphalt in puddles of blood.
Several bodies were taken away in an armored police vehicle.
At least two people who were in a subway car are said to have been injured in connection with a shooting.
24 suspects
One of the victims was police.
The other 24 describe the police as "suspects", something that is questioned by, among others, human rights activists.
- Who's dead?
Young black men.
That is why the police talked about 24 "suspects".
If you are young and black and live in a favela, you are automatically suspected by the police, says Silvia Ramos, head of the security observatory at the Candido Mendes University in Rio de Janeiro, to AFP.
Army-like
The police, for their part, say that the operation was aimed at a criminal gang that is suspected of recruiting children and teenagers for drug trafficking, robbery and murder.
The criminal gang had built up an army-like organization with hundreds of "soldiers" equipped with rifles, pistols, grenades and other military equipment, according to the police.
However, the many casualties and timing of the operation are questioned by critics, as a ruling has banned police from conducting raids on the poor favelas during the corona pandemic, except in "extremely exceptional circumstances."
See the pictures from the operation and hear the reactions from the residents afterwards in the video above.