Brazilians are reacting with outrage to the murder of a prominent councilwoman and human rights activist in Rio de Janeiro, in a blow to President Michel Temer's decision to deploy the military to tackle criminality in the postcard city.
No suspects have been announced by police, but Ms Franco, who was 38, had ruffled many feathers - and that was her mission.
She and her driver, Anderson Pedro Gomes, were both killed, and her press officer, who was sitting in the back seat of the auto, was injured.
Marcelo Crivella, the mayor of Rio de Janeiro, called the murder a "brutal assassination".
Last month, she was chosen to be the speaker of the commission overseeing the deployment of federal security forces into Rio's favelas.
As a black woman who got the fifth highest vote count in Rio's 2016 council elections, Franco stood out in the region's male- and white-dominated politics.
"Another killing of a young man that could be chalked up to the police", she tweeted.
The killing came just weeks after the Brazilian government made a decision to let the military take over all security operations in Rio to control the city's increasing crime rates.
Official figures revealed that on-duty police officers in Rio de Janeiro state killed 1,035 individuals between January and November 2017. "Rio's police are terrorizing and violating those who live in Acari", Franco wrote.More news: Thousands flee besieged enclave in Syria as aid convoy arrives
In one of her last posts on Twitter, Franco had blamed police for the murder of a young man.
Franco, who was raised and lived in the Mare complex of slums, long one of Rio's more unsafe areas, received over 46,500 votes in the 2016 election, the fifth most popular representative out of 51 council members.
Franco grew up in Maré-a complex of 16 favela communities and one of Rio's largest slums-and has been an outspoken advocate for favela residents denouncing police aggression. "How many more will have to die for this war to end?"
As night fell on Thursday, crowds gathered in Rio, Sao Paulo and several other cities, with protesters holding aloft banners calling for justice and an end to Brazil's endemic violence.
The Human Rights Watch has called for a full independent investigation to be carried out.
Franco was a beacon of hope of the people of Rio, which is plagued by a plethora of issues including poverty.
Another police official said that the killers must have known exactly where she was sitting in a vehicle that had tinted windows.
Federal police said in a statement that they were investigating "the origin of the ammunition and the circumstances of the casings found at the scene of the crime". An emergency decree was put into place to combat rising crime as the military took over Rio de Janeiro's security.