Fears over brazil hosting 2016 olympics
Brazil's 6.39bn 2016 infrastructure budget
Rio de Janeiro will host the 2016 Olympic games.
Construction at 2016 Olympics venues has been slow and plagued by difficulties.
IOC says there is concern Rio is falling further behind schedule as unrest builds in Brazil.
Brazilian President proposes a national vote to amend Brazil's constitution after the country's protests.
Pressure is mounting on Brazil to top London’s staging of the Olympics in 2016.