At least 150 inmates broke out of a prison in Brazil's Sao Paulo state, following a riot that set fire to part of the prison.

The riot, that took place in Bauru on Tuesday, is in no way related to a recent spate of violent incidents at prisons in other parts of the country, Military Police Col. Flavio Kitazume said at a press conference, media reported.

According to the state's prison administration agency, police succeeded in recapturing about 100 of the escapees.

Since the start of the year, more than 130 inmates have been killed in prison clashes, which authorities have blamed on organised crime rings, but observers have at least partly blamed on overcrowding in these prisons.  

The prison in Bauru is not as overcrowded as some other jails, according to public news agency Agencia Brasil, housing 1,427 inmates in a facility designed to hold 1,124.

Prison officials said inmates were rebelling against the "strict discipline" at the facility.