Inmates at a prison in Sao Paulo state rioted and took guards hostage, just a day after police quelled Brazil's biggest-ever uprising at other prisons, police said. Authorities said 800 rioting inmates held seven guards hostage at a prison in Pirajui, in the interior of Sao Paulo state, after they refused to return to their cells from their daily sunbathing time. The isolated incident came one day after police put down the most widespread revolt in the history of Brazil's overcrowded prisons, which tore through 29 prisons in wealthy and populous Sao Paulo state, involving 20,000 men. According to Reuters, the death toll related to the mass riots that ended on Monday rose to 19 after three inmates who were being transferred from a rioting prison were found dead from suffocation in a van in the rural interior. Police said there were no deaths on Tuesday in the new riot at Pirajui. Authorities remained tightly focused on Latin America's biggest prison of Carandiru in Sao Paulo city. The sprawling prison, just blocks from the city's downtown area, was involved in the mass uprising and was also the scene of a 1992 police massacre of 111 inmates.