It was a night of bloodshed in the Brazilian city of Sao Paulo as 19 people were killed in a spree of attacks. 

According to witnesses, the shootings took place in several locations in the areas of Osasco, Barueri and Itapevi, and took place when masked gunmen pulled up in a car and opened fire on the victims. 

In many cases, the gunmen asked the victims for their names and criminal records before firing, which has lead authorities to believe that these were targeted killings by other criminal gangs or possibly even rogue police officers, something which is not uncommon in Brazil according to the BBC's Wyre Davies. 

Residents stand across the street from a bar where at least 10 people were shot the night before, in the Sao Paulo suburb Osasco, Brazil. Image: Andre Penner / AP/Press Association Images

While gun violence is a familair part of life in the city, speaking to the Folha da Sao Paulo newspaper, a forensic expert said the scale of the attacks was unprecedented, commenting that "I've never seen so many people killed overnight in Sao Paulo".

According to police, at least 10 of the victims were killed in a bar in Osasco after the attackers got out of their vehicle and opened fire. 

Security Secretary Alexandre de Moraes has said that the attacks were "very serious" and has set up a task force of 50 officers to specifically investigate the shootings, which also injured at least a further seven people.