Updated:Police fire tear gas as they confront protesters in Brazil's largest city Sao Paulo on Thursday. It's day four of demonstrations against an increase in public transport fares. In Rio de Janeiro the crowds were colourful, and largely peaceful. But here in Sao Paulo things turned violent. Local media reports more than 150 demonstrators were arrested. Fares in Sao Paulo increased by nearly 7 percent in June, the equivalent of about $1.50 U.S. dollars.