The ammunition found in the pistol attributed to a lawyer killed by officers of Rota, the elite unit of São Paulo state's Military Police, in Itaquaquecetuba, in the São Paulo metropolitan area, comes from two lots the force bought in 2005 and 2007 that have been feeding crimes for 14 years, according to a survey. The finding is from the Instituto Sou da Paz, a São Paulo-based public security think tank, based on data from a federal prosecutors' investigation, and was reported by the newspaper Folha de S.Paulo on Sunday.

Cartridges stamped with the codes AAE67 and BAY18 were in the magazine of a 9 mm Glock pistol that Military Police officers presented at the police station and attributed to Carlos Alves Vieira, 48, known as Ferrugem. The codes appear in a report by the Instituto de Criminalística, the state forensics institute, and Sou da Paz confirmed the ammunition's origin after a query from Folha, which obtained both the forensics report and the case file. The pistol's serial number had been altered, according to the newspaper.

The lots were huge: AAE67 held 438,000 9 mm rounds, and BAY18 another 320,000 of the same caliber plus 1.4 million .40 rounds. Both broke a 2004 Brazilian Army rule that caps each ammunition lot code at 10,000 rounds. Casings from the same lots have been used in mass killings in greater São Paulo, in an attack that left 11 dead in Londrina, in Paraná state, and in a double homicide in São Gonçalo, in Rio de Janeiro state, the survey found.

A timeline of the case:

• 2004: an Army rule caps ammunition lot codes at 10,000 rounds each.
• 2005 and 2007: São Paulo's Military Police buys lots AAE67 and BAY18, a combined 758,000 9 mm rounds and 1.4 million .40 rounds.
• Past 14 years: casings from the lots appear in mass killings in greater São Paulo, the attack that killed 11 in Londrina and a double homicide in São Gonçalo.
• November 28, 2025: Vieira is killed by Rota officers in Itaquaquecetuba; the case is registered as a death resulting from police intervention.
• December 5, 2025: the police ombudsman's office contests the identification of the dead man and asks for the officers' body camera footage.
• September 6, 2026: Folha publishes the Sou da Paz cross-check linking the ammunition in the case to the police lots.

The killing in Itaquaquecetuba

Vieira was killed on November 28, 2025. The Military Police presented him as Ferrugem, a member of the Sintonia Final leadership circle of the PCC, Brazil's largest criminal faction, and the state Public Security Secretariat (SSP-SP) said he was carrying bricks of marijuana and two pistols and fired first when officers approached his car on Rua Carmo da Mata. The police ombudsman's office, the Ouvidoria da Polícia, received complaints saying he was in fact a lawyer registered with the São Paulo bar association (OAB-SP), the owner of a cardboard packaging company, married, a father of ten and grandfather of two from a traditional family in Poá; according to the office, Ferrugem was a childhood nickname that merely resembled that of the man actually sought by police. The ombudsman asked the Military Police's internal affairs division for the officers' body camera footage, requested from the Civil Police the surveillance images from around the scene and called for the investigation to be moved to the state capital.

"Given these apparent discrepancies, a swift and accurate investigation of the facts is imperative, so that yet another family does not pay with disgrace and the lives of its pillars for unjustified and suspicious acts...", the ombudsman's office said in December.

In a statement, Rota denied any mix-up: it said Vieira was identified through intelligence work, that drugs and two guns were found in his car, and that "another 400 suspects with the same alias Ferrugem are also monitored and appear in the corporation's criminal databases". The SSP-SP maintained that his ties to the PCC were confirmed by its intelligence division, citing 2022 drug trafficking leads from the Denarc police unit in the Alto Tietê region and a prior record for qualified theft. None of those allegations is known to have led to a conviction, and the competing accounts remain under investigation.

The case is being investigated under seal by the homicide unit in Mogi das Cruzes. The Military Police internal affairs inquiry was concluded and sent to the military court, which referred it to the ordinary courts, where it is pending. When asked, the secretariat of the government of Tarcísio de Freitas (Republicanos) said the Civil Police "continues to investigate the November 2025 occurrence in Itaquaquecetuba, including the ammunition used". The next steps are the conclusion of the Civil Police inquiry and the progress of the case in the ordinary courts; no date has been set.