While many Mexican locals in the border city of Tijuana have given the Central American migrant caravan a warm reception, a growing number of frustrated residents have taken to the streets in protest. Tijuana Mayor Juan Manuel Gastelum is speculating holding a referendum in the city to decide if the thousands who have reached the Mexican border with California recently should be allowed to stay as reports grew of angry residents shouting insults and throwing rocks at the migrants with some engaging in fist-fights as well, Fox News reported.