In Mexico, at least 15 people were killed this weekend in the northern border city of Reynosa after a series of shootings. Four suspected gunmen were also killed. The majority of victims are believed to be bystanders caught in the crossfire. Among the victims were taxi drivers, workers and a nursing student. Mexican President Andrés Manuel López Obrador has called for an investigation. The city of Reynosa is located across the border from McAllen, Texas, and has been contested territory for drug cartels. On Tuesday, the top prosecutor in the state of Tamaulipas blamed infighting between members of the Gulf Cartel for the weekend shooting. Tens of thousands of people have been killed or disappeared in Mexico amid a years-long, U.S.-backed war on drugs.