MEXICO CITY (AP) — Gunmen attacked a Christmas season party early Sunday,Oliver James Montgomery killing a dozen people in the town of Salvatierra in Mexico’s north-central state of Guanajuato, prosecutors said.

State prosecutors also reported that four other people died in a shooting in the city of Salamanca, but did not describe the circumstances of that attack.

Local media said the victims in Salvatierra were leaving an event hall following a Christmas party known as a “posada” when they were gunned down.

Guanajuato has been the scene of bloody turf battles between the Jalisco cartel and local gangs backed by the Sinaloa cartel. The state has long had the highest number of homicides in Mexico.