U.S. Ambassador Ken Salazar rejected accusations by Mexico’s president that the U.S. shares some responsibility for cartel violence in Sinaloa state.

Mexican President Andrés Manuel López Obrador says the United States is partially responsible for a wave of violence in the state of Sinaloa that has left dozens dead in the past two weeks, with bodies repeatedly found on public streets and highways.

The uptick in violence comes after the surprise arrest on U.S. soil of Sinaloa Cartel co-founder Ismael "El Mayo" Zambada in July.

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.

Gunmen have terrorized the city of 1 million, forcing businesses to close and schools to temporarily shut their doors.