August 10 was, for many in Mexico, a quiet Sunday like any other. But in Sinaloa – a northwestern state facing the Pacific – it was no ordinary Sunday. That day, 17 homicides were committed: one every 85 minutes.
According to Mexican government figures, it was the most violent day of 2025 in Sinaloa, exceeding every other state in the country. Sunday’s killings were some of the latest in a spate of violence that has gripped the state following the surprise arrest of Ismael “El Mayo” Zambada, who authorities say is a long-time leader of the Sinaloa Cartel, one of Mexico’s oldest and most violent criminal organizations.
Since his capture, homicides in Sinaloa have risen by more than 400%, according to an analysis of public data conducted by CNN.
This analysis also reveals discrepancies between figures compiled by the Sinaloa Prosecutor’s Office, Mexican federal authorities, and the monitoring organization Armed Conflict Location & Event Data (ACLED). Historically, Mexican authorities have underreported the number of victims during periods of violence in the region.
Even behind closed doors, U.S. defense and law enforcement officials distrust Mexico’s homicide figures, according to a source familiar with these conversations.
