Australians are being urged to rethink travel to Mexico after the killing of one of the country’s most powerful cartel leaders triggered a surge of violent reprisals across multiple states — including major tourist hubs.

Nemesio Oseguera, known as El Mencho, was fatally wounded in a military raid in Jalisco and died during an air transfer to Mexico City on Sunday.

The operation, supported by “complementary information” from US authorities, has ignited widespread unrest, with burning vehicles, armed roadblocks and transport shutdowns reported across the country.

The Australian government on Monday issued a fresh alert, warning travellers of “serious security incidents” in Jalisco — including in Guadalajara and the resort city of Puerto Vallarta — following the federal law‑enforcement operation.

Authorities in Puerto Vallarta have issued a shelter‑in‑place advisory, and Smartraveller warns there may be significant transport disruptions, including by air.

Security incidents have also been reported in Tamaulipas, Michoacan, Guerrero and Nuevo Leon.

The Department of Foreign Affairs and Trade continues to advise Australians to exercise a high degree of caution in Mexico overall due to the threat of violent crime.

Travellers are also urged to reconsider their need to travel to the states of Chihuahua, Sinaloa, Guanajuato, Sonora, Colima and Chiapas.

Oseguera, a former police officer, led the Jalisco New Generation Cartel (CJNG), one of Mexico’s most violent and globally connected criminal organisations. His death marks one of the most significant blows to cartel leadership since the downfall of Sinaloa kingpin Joaquin “El Chapo” Guzman.

Experts warn the fallout will be severe.

“A tremendous amount of violence is going to happen,” according to international organised crime specialist Vanda Felbab‑Brown, who compared Oseguera’s influence to Guzman and fellow Sinaloa figure Ismael “El Mayo” Zambada.

Already, the backlash is hitting civilians and tourists.

Videos on social media show cars ablaze and thick smoke pouring over highways, while local media report armed groups blocking roads in more than half a dozen states.

Air Canada has suspended flights to Puerto Vallarta, while United Airlines and American Airlines have cancelled services to both Puerto Vallarta and Guadalajara.

Jalisco Governor Pablo Lemus Navarro has urged residents to stay indoors, and the US embassy has advised its citizens to shelter in place.

With cartel reprisals expected to continue, Australians planning trips to Mexico are being urged to monitor Smartraveller closely, stay alert, follow local advice and be prepared for sudden airport closures, roadblocks and security lockdowns.