Six prisoners were killed on Friday during a riot in a prison in Manaus, the capital of Brazil's northern state of Amazonas, local media reported.

The violence broke out in the prison of Puraquequara for as yet unknown causes, with the six prisoners being found dead in their cells, Globonews reported.

Puraquequara was a part of a series of bloody clashes between two gangs in January, leaving more than 60 prisoners dead.

The Amazonas secretariat of penitentiary administration (Seap) issued a statement that the victims included the right-hand man of the leader of the Familia do Norte criminal gang.

Authorities also decided to transfer around 20 prisoners from the same unit who had received death threats.

On Jan. 1, the prison saw a massive fight between two criminal gangs. Four were killed in Puraquequara while 56 died in the Anision Jobim prison complex, in the same state. The two gangs are in a bitter struggle for control of drug trafficking in the region.

The poor and overcrowded conditions at Brazilian prisons are notorious, and the government has received frequent complaints from NGOs and human rights organizations

Source: Xinhua