Updated

Phoenix Mayor Phil Gordon says seniors, kids and out-of-staters should be wary of the Arizona immigration bill signed into law this past week -- warning that it puts them at risk of being arrested.

The law makes illegal immigration a state crime. It gives police the authority to question people about their immigration status and arrest those who cannot show documentation to establish their legal residency.

Gordon, a staunch opponent of the state law, said that means anyone who doesn't carry an Arizona license -- children under 16, seniors who don't drive and people from out of state -- could be "at risk of being arrested and turned over to (Immigration and Customs Enforcement)."

"It tramples civil rights," Gordon told Fox News on Sunday. "Now everyone has to show and prove that they're a legal resident or citizen."

The mayor of Arizona's largest city is at odds with Arizona Gov. Jan Brewer, who signed the bill Friday and described the legislation as her state's answer to "decades of inaction and misguided policy" in Washington.

It's unclear whether non-state license holders would be as susceptible to arrest as Gordon described.

A "valid Arizona" driver's license is just one of several types of documentation the law says would count as proof of residency.