The killings all occurred in the same neighbourhood of Curitiba, in Parana state A former Brazilian fire chief wanted in connection with a series of murders has turned himself in.
Jorge Luiz Thais Martins is suspected of involvement in the murders of nine drug users in southern Parana state.
The killings happened after his son was murdered by robbers; two suspects in the case, both drug users, were released for lack of evidence.
Police are investigating suspicions that Mr Martins killed them out of revenge, a charge his lawyer denies.
Mr Martins, 56, commanded the firefighters’ department in Parana state from 2007 to 2009.
His son, Jorge Guilherme Marinho Martins, 26, was killed by robbers in October 2009.
Two drug addicts were arrested in connection with the murder at the time, but were released shortly afterwards as there was not enough evidence to link them to the crime.
Following their release, nine drug users were killed and five more attacked in the months between August 2010 and January 2011.
All the killings happened in the city of Curitiba, in the neighbourhood where Mr Martins’ son was murdered.
Police went to Mr Martin’s house on Thursday and seized ammunition which they say is of the same type as that used in the murders.
His lawyer says there is no concrete proof against Mr Martins.
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