McALLEN — Sullivan City’s former police chief received a 10-year prison sentence for his role in a drug trafficking ring busted by federal authorities last year. Hernan Guerra Jr. and seven other men learned their sentences at a hearing Wednesday afternoon in U.S. District Court in McAllen. Guerra’s sentence came after he pleaded guilty for his role safeguarding Mexican drug traffickers moving more than 2 tons of marijuana through Sullivan City. FBI agents arrested Guerra, 45, last June at the Sullivan City Police Department. At Wednesday’s sentencing hearing, it was revealed that investigators had used wire taps to gather evidence...