Updated

Venezuelan officials say at least 15 inmates were killed in a bloody battle among inmates, some of them armed, in a prison in the country's west.

Prisons chief Iris Varela told reporters Tuesday that a 16th person was killed in a different part of the prison in unrelated violence.

Varela said the battle in Sabaneta prison in the city of Maracaibo on Monday appeared to have been for control of the prison grounds.

The interiors of Venezuela's prisons are run by rival bands of inmates, with corrupt guards selling them weapons and drugs.

The nongovernmental Venezuelan Prison Observatory says that last year was the system's worst in 14 years with 591 inmates killed and 1,132 injured.