MEXICO CITY (AP) — Three gunmen pulled up to a party early on Friday in northern Mexico and opened fire on partygoers, killing six people and wounding 26 others.Two of the dead were under 18 years old, and five of the wounded were children. Four of the wounded were reported to be in critical condition at local hospitals, while 13 others were treated and released.ARIZONA BORDER RANCHER FEARS CARTELS INTENTIONALLY OVERWHELM BORDER PATROL AS A ‘DIVERSIONARY TACTIC’Prosecutors in the border state of Sonora said the killings in the city of Ciudad Obregon was an attack on a suspected cartel member who was wanted in homicide and other charges. Mexican border violence has surged of late, as drug cartels battle for territory. (AP Photo/Marco Ugarte)A fourth gunman who participated in the attack was already at the party. The suspected cartel member tried to flee but was killed.CLICK HERE TO GET THE FOX NEWS APPThe attackers were able to escape. Sonora has been the scene of bloody turf battles between various drug gangs.