A Brazilian priest who campaigned for the families of 29 people allegedly killed by rogue police officers has been shot dead.
Paulo Henrique Machado, 35, was shot at least five times while in his car in the Nova Iguacu area of Rio de Janeiro.
He headed a support group for victims of the massacre in March - which led to charges for eight police officers.
The 29 men, women and children were killed when gunmen drove through the city's poor suburbs, firing at random.
Police are investigating whether Machado's death was linked to the massacre.
"The shots came from inside the car, so it was somebody riding with him," said Eleonora Massot, spokeswoman for the security affairs secretariat of Rio de Janeiro.
The Nova Iguacu massacre began when gunmen opened fire on a crowd at a bar killing 17, before going on to nearby Queimados where they killed another 12 people in two separate shootings.
Human rights groups compared the shootings to attacks by death squads, which are said to operate in many areas of Brazil.