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.

Two warring factions of the Sinaloa cartel have clashed in the state capital of Culiacan in what appears to be a fight for power since two of its leaders were arrested in the United States in late July.

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