Political activist Ms Franco and her driver were both shot dead while in her car on Wednesday
Thousands of people in Rio de Janeiro and other cities across Brazil have taken to the streets to mourn a murdered politician who had campaigned against police brutality.
38-year-old Marielle Franco, a Rio city councillor, was viewed by many as a champion of women's rights.
Brazilian President Michel Temer has described her murder as an attack on democracy and the rule of law.
The nation was shaken by Marielle Franco's murder
At a press conference, Public Security Minister, Raul Jungmann said that the federal government will use all resources available to find her killers.
He added,
"I'm here at the request of President Temer.
"I would like to tell the friends of relatives of Marielle that we will find those responsible and punish them for this barbaric crime.
"Justice will be done."
