In São Paulo, the event organized by Movimento Passe Livre, or Free Fare Movement, MPL, turned out approximately 10,000 demonstrators, according to an Anadolu Agency correspondent at the scene. Police put the number at 2,000 at the start of the event, while the MPL said 30,000 protesters participated.
The crowd marched around the city center in protest of the 50 centavo increase to $1.33 (3.50 reais) for bus, local train and metro services.
Although the majority of participants marched peacefully -- some of whom are demanding free public transport for all -- dozens of young demonstrators dressed in black and with covered faces threw trash into the street before they hurled rocks at police, about an hour after the march began.
Riot police responded with volleys of tear gas, stun grenades and rubber bullets before detaining 51 people.
Three banks and two cars were vandalized in the disturbance that lasted more than an hour, with groups splitting off in different directions and the main bulk of protesters dispersing after running from projectiles.
The G1 news portal said around 200 protesters continued to the scheduled end of the protests despite the unrest, and agreed to another event next week.
In Rio de Janeiro, where bus prices recently increased 40 centavos to 3.40 reais, a smaller protest took place.
Most of the 500 demonstrators, according to police figures, were peaceful, but a small minority burned trash in the streets and invaded the famous Central do Brasil rail station, where they symbolically jumped the turnstiles.
Police responded with stun grenades, but the event ended without detentions.
The protests evoked memories of the mass protests in June and July 2013, sparked initially by a hike in bus fares in São Paulo. Those demonstrations were also led by the MPL movement.
The protests quickly ballooned to a point where more than 1 million people took to the streets in more than 300 cities across Brazil, the biggest demonstrations in a generation.
Apart from transportation costs, many other agendas were also brought into the mix, from demands for political reform to calls for better public services, particularly health and education.
President Dilma Rousseff sought to placate protesters and vowed to work toward political reforms and provide more funding for public services, something she reiterated during her Jan. 1 inauguration address.
Israeli army frequently conducts wide-ranging arrest campaigns in the occupied West Bank
Probe by Israeli rights group B'Tselem concludes that intentional fatal shot was fired at the Palestinian paramedic.
"I accept our intelligence community's conclusion that Russia's meddling in the 2016 election took place," Trump said
Here are five takeaways from the news conference that followed their first summit, in the Finnish capital Helsinki:
An abandoned mining town in California went on sale for $ 1.4 million
Roughly 80 percent of Iraq’s crude oil exports originate from oilfields in Basra province
Kerem Shalom is Gaza's only functioning commercial crossing
More than 130 Palestinians have been killed by Israeli fire since March
Resources strained as thousand crossing into Canada from US
American Civil Liberties Union granted request to halt deportations for one week after reunification
Trump declared that US-Russian relations have turned a corner after a summit with his Russian counterpart Vladimir Putin that he described as "open, direct and deeply productive".
Operation is aimed at restoring confidence after last year’s illegitimate poll on Kurdish regional independence
The U.S. State Department is negotiating a potential deal to sell Turkey the Raytheon Co Patriot missile defense system as an alternative to the Russian-made S-400 system Turkey has agreed to purchase, an official said on Monday.
ISIL still maintains a limited presence in northern and western Iraq
90 more migrants in critical condition found inside shipping containers