The mutilated and dismembered bodies of 12 people were found dumped in seven locations across the Mexican city of Monterrey today in a wave of violence that has unsettled residents of the country’s industrial capital.

The grisly findings evoke memories of the bloody period in the 2010s when cartel feuds dominated the city and bodies were found lying in the streets or hanging from bridges.

That brutality has largely subsided in Monterey, which was recently chosen as the site for Tesla’s new car factory.

Authorities said Tuesday’s events appear to be a coordinated attack and may have been sparked by an internal dispute within a criminal organization based in the state of Tamaulipas.

“From the messages found (near the bodies) there is some correlation,” said Pedro Jardon, the Nuevo Leon state prosecutor in response to questions from reporters yesterday afternoon.

Photographs of the alleged messages circulated in the local press and on social media suggest the killings were carried out by the Northeast Cartel and were in retaliation for the group’s alleged infiltration.

The prosecutor’s office has not confirmed the authenticity of the photos.