A car bomb exploded in front of a police station in Mexico Sunday night, wounding six people, authorities said.Zacatecas is key to the drug trade because it links central Mexico with the north and west of the country and features routes that are key to smuggling cocaine and other narcotics to the United States. (Shutterstock/Representational)The blast happened in the town of Ojocaliente in Zacatecas, a state with key routes for drug trafficking."The explosive was placed in a private vehicle and caused physical damage to the station and properties located nearby," state government secretary Rodrigo Reyes said on Facebook."Six civilians have been reported wounded, who are receiving medical care," he said in an earlier post.Also Read | US revokes visa of former Mexico President's son: What led to the decision and why López Beltrán is questioning TrumpZacatecas is key to the drug trade because it links central Mexico with the north and west of the country and features routes that are key to smuggling cocaine and other narcotics to the United States.Horrific drug violence plagued the state for years, with bodies turning up and people going missing almost on a daily basis until relative calm set in.But in July, five bodies appeared hanging from a bridge in the town of Pozos de Gamboa, about 75 kilometers (47 miles) from Ojocaliente.The victims included a former mayor, civil servants and business people from other parts of the state.