The violence erupted in the city of Milagres, in the northeastern state of Ceara, with a fierce pre-dawn shootout between the armed robbers and the police.
He said four of the hostages, including the child, were all from the same family. They had been grabbed by the fleeing robbers as they were going to the nearby airport to catch a flight.
Landin said that "the criminals killed the hostages and the police killed the criminals." Some Brazilian media gave higher death tolls, of up to 13, and said the child killed was a 14-year-old boy.
The attempted robbery of the two banks occurred at 2:17 am (0417 GMT). When police arrived a shootout lasting 20 minutes ensued, reports said.
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