Gunmen shot and killed at least 14 people early Saturday in a crowded dance club in the northeastern Brazil city of Fortaleza, authorities said.

At least another six people were injured and are hospitalized in Fortaleza, said Andre Costa, who heads the Ceara state security secretariat, which oversees police forces.

The shootings took place near the Arena Castelao soccer stadium that was used in the 2014 World Cup of soccer.

Costa told journalists that a motive was not yet known, but authorities were investigating whether the killings were part of an ongoing fight between two drug gangs.

No suspects are in custody.

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A look inside the nightclub, after the shooting. In its reporting of the attack early Saturday, the EFE news agency said there were about 5,000 homicides recorded in the state of Ceara last year, an increase of 47 per cent over the previous year. (Rodrigo Carvalho/AFP/Getty Images)

Eyewitnesses told the Globo TV network that three cars full of armed men arrived at the dance club around 12:30 a.m. and fired rounds into the front of the building for at least a half-hour before fleeing.

Brazil routinely has more homicides per capita than any other nation, according to an annual United Nations compilation of violence. In recent years, homicides have increased significantly more in the country's northeast area than in the rest of the nation.

With files from the Associated Press and CBC News