The governor of a western Mexican state says a mayor and four local police officers have been arrested in the murder of 10 people who were killed and burned over the weekend.

Michoacan Gov. Silvano Aureoles said in an interview with Imagen Radio Tuesday that authorities initially thought the bodies found in a pickup near a gas pipeline in Cuitzeo had been somehow related to illegal pipeline taps.

However, Aureoles says that the investigation eventually revealed that police from the town of Alvaro Obregon had detained the victims. He says interviews point to the mayor of Alvaro Obregon as the one who gave the order.

He says the motive appears to be related to a rivalry over street-level drug sales. The mayor has been transported to prison.