Arizona Gov. Jan Brewer has signed controversial immigration reform for her state into law, despite concerns that it will lead to racial profiling and unfair treatment.
As thousands gathered in protest throughout the state, Brewer gave her "unwavering signature" and "steadfast support" for tackling Arizona's immigration issue.
"We in Arizona have been more than patient-- waiting on Washington to act," she said.
Brewer called the conditions in Arizona "dangerous" and "unacceptable," because of inaction from the government.
The new immigration enforcement law will make it a crime to be in the country illegally. The law also allows police officers to question people they suspect to be in the country illegally.
Brewer said the new law has been revised so that there will be no racial profiling or discrimination, but many aren't convinced.
She did issue an executive order requiring new police training so that officers know what "does and does not constitute" ways of determining if a person is illegally present in the United States.
Earlier Friday, President Barack Obama expressed concern about the Arizona legislation, calling it a "misguided" measure that could violate individual rights.
"I've instructed members of my administration to monitor the situation and examine the civil rights and implications of this legislation," Obama said. "But if we continue to fail to act at a federal level, we will continue to see misguided efforts opening up around the country."
Arizona has the most border crossings of any state, with an estimated 460,000 illegal immigrants.
The bill was sponsored by GOP Rep. Russell Pearce of Mesa. He said making the legislation law will lead to improvements in nearly every area.
"We'll have less crime. We'll have lower taxes," he said. "We'll have safer neighborhoods. We'll have shorter lines in the emergency rooms. We'll have smaller classrooms."
The new immigration law is expected to be challenged.