They say it's an attempt to skirt a new law that prohibits elected officials from using government advertisements to promote their own careers.
An opposition city councilman is considering filing a complaint in the case, saying the man pictured in the ads looks so similar to Mayor Juan Sanchez, that it seems like a computer-altered picture of the mayor.
Sanchez dismisses the accusation, saying a model was hired for the shoot.
He says people tell him he's actually more handsome than the guy on the billboard.
The law was touted by the Mexican Congress as the end of an era in which politicians took personal credit for public-works projects.
