MEXICO CITY Mexico warned its citizens living in or traveling to Arizona that they could be "harassed" there after the state passed one of the toughest immigration laws in the United States last week.
Arizona's Republican Governor Jan Brewer signed a bill into law last week that makes it a crime to be in the state illegally and requires police to check the status of people they reasonably suspect to be illegal immigrants.
The law, decried by critics as discriminatory, will force immigrants to carry their alien registration documents at all times once it takes effect 90 days after Arizona's current legislative session ends.
Mexico's foreign ministry issued a statement saying that Mexicans in Arizona should be aware of the new law and contact their consular representatives if they are unlawfully detained.
"Until it is clearly defined under what criteria, when, where and who the authorities will check, you should assume that every Mexican citizen could be harassed and questioned without cause at any moment," it said.
The new law prohibits people from being hired from a vehicle on a public street, the statement noted. Undocumented workers in the United States often gather to wait for employers to drive by and pick them up for day jobs as construction workers, farm workers or landscapers.
An estimated 460,000 illegal immigrants live in the desert state, which also straddles the main point of entry for illegal immigrants crossing into the United States from Mexico.
President Barack Obama denounced the Arizona law as misguided and has ordered monitoring of its implementation. White House press secretary Robert Gibbs has warned that other states could also bring in tough immigration laws if there is no national comprehensive immigration reform.
Mexican President Felipe Calderon has said the law criminalizes immigration and opens the door to "intolerance, hate, and discrimination.
To protest against the law, the governor of the Mexican border state of Sonora canceled a June meeting with Arizona officials that would have been the latest in decades of annual cooperation meetings between the two states.
The legislation sparked street protests and has forced hard choices on immigrants, some of whom have lived in Arizona for years.