Several Palestinian activists were arrested in downtown Sao Paulo on Tuesday night after clashing with members of a far-right group who were protesting a new immigration bill, according to police.
Four of the men were charged with assault, criminal association, causing an explosion and resisting arrest and as of Wednesday afternoon were awaiting custody hearings.
Protests over immigration and refugees are a rarity in Brazil, which has generally welcomed immigrants.
The immigration bill — which was passed by Brazil's Senate last month and needs approval from President Michel Temer to become law — has not been controversial. It eliminates some of the red tape involved in getting legal documentation and joining the workforce, removing discriminatory language adopted by the military dictatorship that ruled the country from 1964 to 1985.
Brazil is home to 1.5 million to 2 million immigrants, including as many as 600,000 in Sao Paulo. They come from nearly every nation.
Brazil has open-door policy when it comes to Syrian refugees. In 2013, it created a special humanitarian visa for those escaping the war there and as of last June issued 8,450 of them.
Many Syrian refugees in Brazil say they feel comforted by its long-standing Syrian and Lebanese communities, which arrived in two waves of migration — first in the 19th century, then after World War I — and today are concentrated in downtown Sao Paulo.
Significant numbers of refugees also come from Angola, Nigeria and the Democratic Republic of Congo, according to the Catholic charity Caritas, which provides services to them.
The anti-immigrant protest Tuesday was organized by two groups — the Free Brazil Movement and Right Sao Paulo — to urge Temer not to sign the bill.
Protesters appear in videos posted on social media calling Palestinians and other immigrants "lazy-ass communists" and saying "communists have to die" and "those rats hit women" while cheering on police officers breaking up fights and making arrests.
Right Sao Paulo posted a video on its Facebook page purporting to show "a terrorist attack" in which someone of Arabic descent threw a homemade bomb. But it is unclear from the video what was thrown or who threw it.
The protest took place on Sao Paulo's main business stretch, Paulista Avenue, the same place where Right Sao Paulo held a rally in November to celebrate Donald Trump's victory in the U.S. presidential election.
Local media reported that one man was taken to a hospital with a possible nose fracture and other injuries after the violent confrontation.
Among those arrested was Hasan Zarif, leader of the Palestine for All Movement and owner of Al Janiah, a restaurant run by refugees and known for supporting activism in favor of immigration from the Middle East. In a show of solidarity, 50 people spent the night in front of the police station where the detainees were taken.
None of those who organized the anti-immigration protest were detained.