BIRMINGHAM, Alabama — Parents who entered the United States illegally so fear for their future in Alabama that many are drawing up legal custody papers in case they have to leave their children behind following deportation.

"They could just run us out of the country when we are out in the street with the kids," fretted Ruben, who asked that his family name not be used.

But "now I have found a job, and I have three kids to support. I can't just leave out of fear. We have to tough it out," the Mexican migrant said.

His answer: to spell out legally what happens with his kids if the worst happens to him and his wife, Marina.

A federal appeals court last week blocked provisions in the nation's toughest immigration law that required schools to check whether students were in the United States legally or not, and required immigrants to carry an alien registration card.

But it also backed new police powers for detaining anyone suspected of being illegal immigrants, as well as provisions making it illegal for undocumented immigrants to enter into business transactions.

Since Alabama's state law HB 56 took effect September 28, thousands of families have all but stampeded out of Alabama, social and humanitarian groups here said.

Still others have decided to stay and live in fear. They desperately strain to stay below the radar, for example buying more food less often so that they can leave home less often.

Ruben and Marina are among more than 500 families that sought out legal aid to set up power of attorney paperwork in case they should be whisked out of their children's lives.

US-born children do not have to leave the country but parents being deported may have to decide if their kids should be left alone abroad.

"We like to go shopping together, the five of us. And it is far away. So (fearing that we might be caught and deported), we had a power of attorney drawn up," Marina said, adding hopefully: "God help us!"

Among the legal issues parents are scrambling to try to plan for: who will care for their children in case of an unwanted family separation, and who will care for homes they may have bought, the advocacy group Hispanic Interest Coalition of Alabama said.

The group said it had about 20 visits a day before the law was passed, and that the volume surged to 70-100 visits a day since it took effect.

Ruben works eight hours a day seven days a week taking care of a golf course for 7.60 dollars an hour. "We can't go back to Mexico because we are very poor there, and in most of the United States things are bad too, so for now, we have to stay here," explains Marina.

Miguel, a construction worker, said he was trying to arrange legally for his sister in a neighboring state to come collect to Alabama to get his children in case he is picked up and deported.

"I am having trouble sleeping, having nightmares about being caught and deported. And the worst thing is imagining what could happen to my kids," he said.

Vanessa Stevens, a spokewoman at HICA, said HB 56 "is making impossible the everyday life of immigrants ... It is sad to say, but that's the goal of this law, they want immigrant out of here."

"Many people fled for fear and that is hurting our local economy and our reputation as a state in the country and in the world," Stevens said.

Nationwide, there are an estimated 11 million undocumented immigrants in the United States, most of them from Latin America and the largest group from neighboring Mexico.

The Pew Hispanic Center, the top US institute for the study of the Hispanic community, estimates that in Alabama there are 130,000 undocumented immigrants.

Though Arizona proposed the first immigration law that criminalized undocumented aliens, its most controversial provisions, such as empowering the police to question a person's immigration status, were blocked by the courts.

But other states have followed suit with their own laws in defiance of Washington.

The legislation has not been without cost. In Georgia and Alabama, a shortage of workers has appeared in key sectors including agriculture as immigrants head for the borders.