Events: Topics: The Battle of Doctor Coss was an armed conflict in Mexico between the Gulf Cartel and the Cártel del Noreste faction of Los Zetas in the municipality of Doctor Coss, Nuevo León.

The confrontation was one of the most serious in the region, disputed by both cartels due to their proximity to border municipalities of the neighboring state of Tamaulipas.

[7] The attackers ambushed the police command with assault rifles, fired from vans with artisanal armor.

[10] In a study carried out by the Consejo Ciudadano para la Seguridad Pública y la Justicia Penal (Citizen Council for Public Security and Criminal Justice in Spanish), it was detailed that the proximity to the border municipalities causes the climate of violence, which according to the study made it the most violent municipality in Mexico with 1,691 per 100 thousand inhabitants (with only 1,360 inhabitants and 23 murders in 2021).

[2][11] On 15 october 2021 the city was the scene of a violent battle between the two cartels in which about ten narco tanks were used.