SAO PAULO (Reuters) - The state of Sao Paulo is considering transferring four leaders of Brazil’s most powerful drug cartel to federal prisons and stricter jail terms for 12 jailed leaders following an outbreak of gang-related violence across prisons, O Estado de S. Paulo newspaper reported on Saturday.

According to the paper, which did not say how it obtained the information, the state is analysing whether to ask federal authorities to keep as many as 12 jailed leaders of the PCC gang under a so-called strict disciplinary regime for a year.

One of the targets of the disciplinary action would be Marco Herbas Camacho, known by his alias of “Marcola” and the PCC’s most prominent leader, Estado said.

Calls to a Sao Paulo state spokeswoman seeking comment were not immediately answered.

This month’s killing of dozens of inmates by fellow prisoners in Brazil’s deadliest jail uprising in decades has exposed escalating turf wars between the PCC and the rival Comando Vermelho that risk plunging a chaotic penitentiary system deeper into violence.

An overall lack of security and lax law enforcement where authorities have long tolerated high homicide rates has left Brazil as the world’s No. 4 country in terms of the number of inmates.