A prominent Brazilian conservationist and his wife have been killed in the Amazon region, police have said.
They said Joao Claudio Ribeiro da Silva and Maria do EspIrito Santo da Silva were ambushed in Para state, near the city of Maraba.
The environmentalist had repeatedly warned of death threats against him by loggers and cattle ranchers.
News of the killings came hours before Brazil's Chamber of Deputies passed a law that eases deforestation rules.
The government has ordered an immediate investigation and promised to catch those responsible for the deaths of Mr Da Silva and his wife.
The bodies of the couple were found inside the nature reserve, Praialta-Piranheira, where they had been working for the past 24 years.
According to family and friends, the pair had been subjected to numerous threats in the past two years for their environmental activism.
They made a living with eco-friendly cultivation of nuts, fruit and rubber.
News of the deaths came just hours before Brazil's Chamber of Deputies voted on changes to the existing Forest Code.
The legislation, first enacted in 1934 and subsequently amended in 1965, sets out how many trees farmers can cut down.
Regulations currently require that 80% of a landholding in the Amazon remain forest, 20% in other areas.
The new bill, which now needs approval from the Senate and President Dilma Rousseff, reduces the amount of land farmers must keep as forest.
Other changes include some amnesties for those who have illegally cleared land in the past.
Proponents of change argued that the law impeded economic development and said that Brazil had to open more land for agriculture.
Opponents described the legislation as a "disaster".
"It heightens the risk of deforestation, water depletion and erosion," Paulo Gustavo Prado from Conservation International-Brazil told Reuters.