The shooting happened in the city of Milagres, state of Ceara, when a group of 30 armed individuals attempted to assault two banks using hostages, but were surprised by police.
Lielson Landim, the mayor of Milagres, said that before arriving in the city's center to commit the bank robbery, the assailants stole a truck to block one of the city's main streets.
Upon being discovered by police, a fierce gun fight broke out and lasted 20 minutes. At least three minors, who were being held as hostages along with their parents, died.
Several of the bank robbers managed to escape and police began an operative in the region to capture them.
At least six of the dead were the robbers and the rest were hostages, Landim said.
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