When was the last confirmed cartel violence against any US LEA on US soil?

Cartel leadership have openly stated that any such thing would be the height of counterproductive stupidity on their part due to the overwhelming response that it would elicit.

The last confirmed incident was in the 90s. There was an incident in Texas a couple of days after Trump was inaugurated but this seems a little lacking in concrete details or threat: across the river, no video evidence, no injuries, no bullets recovered, no suspects, no identification, just a broad "description" of the shooters as "likely cartel members".