A riot at the El Castillo prison in Mazatlán, in Mexico’s Sinaloa state, left 10 people dead on Thursday 8 October. Nine of the dead were inmates and one was a visitor.
Mazatlán is a Pacific port and resort city, and Sinaloa’s security situation is closely followed in the United States. The Sinaloa State Public Security Secretariat says the prison is now under control.
Sixteen inmates were injured in the fighting and moved for medical care. Authorities have not yet said what started the violence.
Key Facts
—Who. Nine inmates and one visitor died; 16 inmates were injured.
—What. A riot (“riña”, a brawl between inmates) at the El Castillo prison.
—Where. Centro Penitenciario El Castillo, Mazatlán, Sinaloa state, Mexico.
—When. Thursday 8 October 2026.
—Official line. Sinaloa authorities say the prison is under control; family visits are suspended.
—Status. As of 9 October 2026, 01:30 GMT
What We Know
The riot took place at the Centro Penitenciario El Castillo in Mazatlán on Thursday 8 October. The Sinaloa State Public Security Secretariat (SSP Sinaloa) and the prison management reported the incident.
Mazatlán lies on Mexico’s Pacific coast in Sinaloa state. The reports place the incident inside the prison, not in the city’s tourist areas.
Officials described it as a “riña”, the Spanish word for a brawl or fight between inmates. Proceso and Noroeste, two Mexican news outlets, put the toll at 10 dead and 16 injured.
The dead are nine inmates and one visitor, a person who had come to see an inmate. Authorities have not released their names.
Sixteen inmates were injured and transferred for pre-hospital medical care, meaning emergency treatment given before hospital admission. The authorities have not said how serious the injuries are.
Officials say the prison “is under control” and that officials remain present to guarantee safety. An interagency group, known in Spanish as the Grupo Interinstitucional, intervened at the prison.
Family visits have been suspended as a precaution. The authorities report that the remaining inmates are in good condition.
The Sinaloa State Attorney General’s Office, the Fiscalía General del Estado, is investigating and will determine responsibility. No arrests or suspects have been reported so far.
Proceso reports that local sources heard gunfire inside the facility. We treat that as a report from those sources, not an official finding.
The Public Security Secretariat is Sinaloa’s state security agency. Its statement is the primary source for this report, and the three outlets cited below relay it.
El Castillo has seen deadly violence before. Two weeks earlier, on 24 September 2026, two inmates died after a fight in the workshop area, according to SSP Sinaloa.
What Is Not Known
Officials have not said what caused the riot. They have not named the groups or inmates involved.
Officials have not explained how any weapons entered the prison. The gunfire account comes only from local sources cited by Proceso.
The identities of the dead have not been published. The final toll could change as authorities update their counts.
The sources we reviewed do not say whether any prison staff were hurt. They also give no timetable for the investigation’s findings.
Outlets differ on the time of the riot, so we give no clock time. It is also unclear whether the 24 September fight is linked to this one.
What It Means for Travelers and US Readers
The violence took place inside the prison, and the reports we reviewed describe no risk to visitors outside it. That is a statement about what has been reported, not a guarantee about conditions across the city.
US travellers should check the State Department’s travel advisory for Sinaloa before booking or travelling. We do not state its current level here, so readers should consult the official page.
Expats and residents should follow SSP Sinaloa for updates. Relatives of inmates face a practical effect, because family visits are suspended for now.
For US readers who follow Mexican security, the case shows how quickly an official toll can move in the first hours. Treat every figure as provisional until the Attorney General’s Office confirms it.
This report relies on official statements and three Mexican outlets, and we have not independently verified the toll. We will correct it if authorities revise their figures.
Authorities have not yet set out a timeline for lifting the visit suspension. Further coverage of the country is on our Mexico page.
Frequently Asked Questions
What happened at El Castillo prison in Mazatlán?
A riot, described in Spanish as a “riña”, broke out among inmates at the El Castillo prison on Thursday 8 October. The Sinaloa State Public Security Secretariat says the prison is now under control.
How many people died and how many were hurt?
Ten people died, nine inmates and one visitor, and 16 inmates were injured, according to the Sinaloa State Public Security Secretariat as reported by Proceso and Noroeste. The toll could change as authorities update their figures.
Who is investigating the riot?
The Sinaloa State Attorney General’s Office, the Fiscalía General del Estado, is investigating and determining responsibility. An interagency group intervened at the prison, and family visits have been suspended as a precaution.
Should US travellers check advisories for Mazatlán?
The reports describe the violence as inside the prison and mention no risk to visitors outside it. US travellers should still check the State Department’s travel advisory for Sinaloa before they travel.
Sources
Primary source: Sinaloa State Public Security Secretariat statement, as reported by Proceso · Aristegui Noticias · Noroeste
This article was produced by The Rio Times’ automated newsroom system. How we use AI · Report an error · Editorial responsibility: Matthias Camenzind, Editor-in-Chief