Updated at 12:55 a.m. ET
Thousands of people from around the country descended on the Phoenix area Saturday as supporters and opponents of Arizona's tough new crackdown on illegal immigration held separate rallies.
Marchers carrying signs, banners and flags from the United States and Mexico filled a 5 mile stretch of central Phoenix, demanding that the federal government refuse to cooperate with Arizona authorities trying to enforce the law.
Police declined to estimate the size of the crowd, but it appeared at least 10,000 to 20,000 protesters braved 94-degree heat. Organizers had said they expected the demonstration to bring as many as 50,000 people.
Opponents of the law suspended their boycott against Arizona and bused in protesters from around the country. Some used umbrellas or cardboard signs to protect their faces from the sun. Volunteers handed out water bottles from the beds of pickup trucks, and organizers set up three water stations along the route.
About 20 people were treated for heat or fatigue-related symptoms, and seven of them were taken to a hospital, said Phoenix police spokesman Sgt. Tommy Thompson. There were no arrests or other incidents, he said.
The law's opponents also gathered at capitols in states including Texas and Oregon, and about 300 people protested at the U.S. Embassy in Mexico City demanding legalization for undocumented Mexican workers in the United States.
"Many of us have relatives or friends in the U.S. and we must now stand up and speak out on their behalf," said Elvira Arellano, who gained international attention in 2007 when she was deported without her U.S. citizen son.
In San Francisco, about 500 people gathered Saturday night outside AT&T Park, where the Giants were playing the Arizona Diamondbacks. Leaders of the rally said it was organized to help push for a boycott against Arizona.
About 7,000 supporters of Arizona's law gathered Saturday evening at a baseball stadium in suburban Tempe, encouraging like-minded Americans to "buycott" Arizona by planning vacations in the state.
Charlene Pellin answered that call. The 64-year-old suicide prevention speaker drove to Phoenix for a four-day vacation from her home in Huntington Beach, Calif., to attend Saturday's rally.
"Hopefully if enough people show support for Arizona more states will follow suit," Pellin said.
Supporters said they are standing with Arizona for trying to enforce immigration laws because the federal government has failed to do so.
"The operative word in all this is 'illegal,'" said Christine Griswold, a 54-year-old gynecologist in Palm Desert, Calif. "It has nothing to do with their race. It's that they're coming to the country illegally."
The law requires that police conducting traffic stops or questioning people about possible legal violations ask them about their immigration status if there is "reasonable suspicion" that they're in the country illegally.
Critics of the law, set to take effect July 29, say it unfairly targets Hispanics and could lead to racial profiling. Proponents insist racial profiling will not be tolerated, but civil rights leaders worry that officers will still assume illegal immigrants are Hispanic.
"I don't think that this law is American. I think it's discriminatory," said marcher Chelsea Halstead, a 20-year-old college student from Flagstaff. "I'm offended by it because this is a nation founded by immigrants."
Some marchers chanted "si se puede," a phrase coined by Hispanic civil rights leader Cesar Chavez that roughly means "yes we can." Others took aim at President Obama, demanding that he prioritize comprehensive immigration reform that would create a pathway to citizenship for illegal immigrants now in the country.
"Obama, listen, we are in the fight," they chanted in Spanish. A handful of protesters also carried a massive banner that read: "Where's the change? Mr. President how can we trust you for re-election?"
Alfonso Martinez, a 38-year-old Phoenix carpenter and father of three children who are American citizens, said he's been living illegally in the United States for 21 years while trying to get legal status.
"If they stop me and they find my status, who's going to feed my kids? Who's going to keep working hard for them?" he said, keeping a careful eye on his 6-year-old daughter as his wife pushed their 4-year-old girl in a stroller. Their 13-year-old son walked ahead of them.
Luis Jimenez, a 33-year-old college professor who lives in South Hadley, Mass., said the law will force police officers to spend much of their time on immigration violations instead of patrolling neighborhoods or dealing with violent crime.
The law also makes it a state crime to be in the country illegally or to impede traffic while hiring day laborers, regardless of the worker's immigration status.
"You're saying to the cop: 'Go pick up that day laborer. Don't worry about that guy committing crimes,'" said Jimenez, a naturalized citizen from Mexico who grew up in Phoenix.
More Arizona Immigration Coverage
DOJ, Arizona Officials Meet over Immigration Law
Opinion: Immigration and American Power
Dems Stop Bid for 6,000 More Troops at Border
On the Web
Arizona Law Opponents: http://www.altoarizona.com
Arizona Law Supporters: http://www.standwitharizona.com
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