At least 14 people were killed overnight in a shootout at a nightclub in Fortaleza, northeastern Brazil, officials said on Saturday.

“We can confirm 14 deaths,” Andre Costa, security secretary for the state of Ceara — of which Fortaleza is the capital — told a press conference.

Costa said that other victims are hospitalised in serious condition, but did not say how many people were injured.

A spokesperson from the Institut Jose Frota hospital told AFP that six people, including a 12-year-old boy, had been rushed in for emergency care.

The shooting broke out in the morning when a group of armed men arrived in three vehicles at the Forro do Gago nightclub in Fortaleza's Cajazeiras neighbourhood.

“It's a brutal scene, a massacre. Something you never see in Ceara,” a police officer, who asked to remain anonymous, told news website G1.

Local media reported that the shootout was a clash between members of two rival drug trafficking gangs.

Officials, however, remained tight-lipped. “The investigation is still ongoing,” Costa said.

On January 7, a war between drug gangs already claimed four lives in the suburbs of Fortaleza. Last year there was a record 5,114 murders in the state of Ceara, a 50 per cent rise from 2016.