Cartel Jalisco New Generation (CJNG) gunmen lined up at least 17 victims and shot them during a funeral in western Mexico Sunday.

The case took place in Marcos Castellanos, Michoacan, where gunmen stormed a funeral service and forced mourners to line up against a wall before opening fire.

Viral videos captured the gruesome execution on social media.

One of the working law enforcement theories suggests the gunmen were targeting a former ally attending his mother’s funeral. The Michoacan Attorney General’s Office revealed that the bodies were removed and the scene was largely cleaned by the perpetrators. However, authorities did find bullet casings.

State and federal authorities have been unable to stop a fierce war in Michoacan between the CJNG and Carteles Unidos, an alliance of smaller regional organizations with proxy support from the Sinaloa Cartel.

Ildefonso Ortiz is an award-winning journalist with Breitbart Texas. He co-founded Breitbart Texas’ Cartel Chronicles project with Brandon Darby and senior Breitbart management. You can follow him on Twitter and on Facebook. He can be contacted at Iortiz@breitbart.com

Brandon Darby is the managing director and editor-in-chief of Breitbart Texas. He co-founded Breitbart Texas’ Cartel Chronicles project with Ildefonso Ortiz and senior Breitbart management. Follow him on Twitter and Facebook. He can be contacted at bdarby@breitbart.com.