Security cameras captured the moment two hooded men got out of a car with submachine guns and opened fire outside the airport terminal.
Gritzbach, a PCC graduate, dropped his bag and tried to run away, but was shot multiple times and died at the scene.
Gritzbach, a cryptocurrency expert, was in the process of telling officials how he helped the gang launder millions of dollars.
According to Brazilian media reports, he was once considered a key figure in gang activity.
As part of his plea deal, Gritzbach promised to help investigators find other members and turn over documents.
In return, Sao Paulo prosecutors reportedly offered Gritzbach a pardon and a reduced sentence on money laundering charges.
The PCC was formed in the early 1990s and has since become one of Brazil’s most feared drug gangs. However, membership is not limited to Latin America.
A report from Portugal’s security service last year showed the group had 1,000 employees in Lisbon, the European country’s capital.
Sao Paulo’s organized crime task force estimated that in 2023 the PCC would make nearly $1 billion (£773,000) from international cocaine trafficking.
