The U.S. ambassador to Mexico on Saturday rejected President Andres Manuel Lopez Obrador's claims that the U.S. was "co-responsible" for violence in the western state of Sinaloa, where more than 50 people have died in an intra-cartel war this month.

Mexican President Andrés Manuel López Obrador has blamed the United States in part for the surge in cartel violence terrorizing the northern state of Sinaloa which has left at least 30 people dead in the past week.

Some 53 people have been killed and 51 others are missing in Mexico's western Sinaloa state since rival factions of the Sinaloa Cartel began clashing on Sept 9, local authorities said on Friday, with gruesome violence showing no signs of abating.

Mexican President Andrés Manuel López Obrador is asking the warring factions of the Sinaloa cartel terrorizing the capital city of Culiacán to act "responsibly” so no one else gets killed

Shootouts in the western Mexican state of Sinaloa have kindled fears that an intra-cartel war is about to break out in the wake of the arrest of legendary trafficker, Ismael "El Mayo" Zambada, in July.

Mexican leader says the U.S. bore some responsibility "for having carried out that operation" to arrest Ismael 'El Mayo' Zambada.

Two warring factions of the Sinaloa cartel appear to be fighting for power since two of its leaders were arrested in the U.S.