A total of 29 inmates were killed Monday in a prison riot in the northwestern city of Mazatlan in Mexico's Sinaloa state, officials said.
Meanwhile, at least ten police officers died on the same day in two ambushes by unknown gunmen in the central city of Zitacuaro in Michoacan state.
Sinaloa State Public Security Secretary Josefina Garcia confirmed that 18 inmates were shot dead and 11 others were stabbed to death during clashes between rival drug gangs over the control of a prison in Mazatlan. At least three guards and other several prisoners were injured.
When the riot was brought under control, police found seven firearms, eight metal objects point and an ice pick as well as 182 used bullet shells. Sinaloa is home to the Sinaloa drug cartel.
The violence began in the morning when inmates tried to rush guards during shift-change in a bid to stage a massive jailbreak.
The facility was known as the Mazatlan Center for the Execution of Crime’s Legal Consequences, which houses 1,650 convicted criminals.
The Mexican army has taken control of the prison and order has been restored. Surrounding streets are being patrolled by army and police, while local authorities is requesting a transfer of most of the inmates to other places.
Michoacan state police said the slain officers had finished patrol and were headed to Mexico City when they came under attack. The officers returned fire, killing some gunmen and wounding several others. At least 15 officers were also wounded in the attacks.
Michoacan is home base of the La Familia drug cartel and a crucial front in President Felipe Calderon's campaign against organized crime.
Mexico has been torn by drug-related violence in recent years.