OKLAHOMA CITY (AP) - A new law to fight illegal immigration will not change anything immediately for the two largest state agencies that administer public benefits to poor people.

The law, which went into effect on Thursday, was billed as a way to curb public benefits going to undocumented workers.

However, spokeswomen for the Department of Human Services and the Oklahoma Health Care Authority said their agencies already comply with federal guidelines on who can receive those benefits.

They said nothing in the new law will change the way they operate.

The law is blamed for widespread fear among growing Hispanic communities, causing thousands of undocumented people to flee the state.

A federal judge on Wednesday denied a request by Latino groups to block the implementation of the law. In a two-page ruling, U.S. District Judge James H. Payne wrote that the plaintiffs had failed to introduce enough evidence to meet the burden of proof required for a preliminary injunction to be issued.

DHS spokeswoman Mary Leaver said the law could add to the state's welfare costs if undocumented workers, who also are their families' breadwinners, are deported or leave the state.

Families with an undocumented parent do not now qualify for welfare payments or food stamps. They could qualify in the future if an undocumented worker leaves the state, leaving behind a spouse or children who are legal residents, Leaver said.

She said the DHS will be watching to see if there is an increase in applications for assistance. “It would be very hard to speculate or to guess what the future will hold, but we do have that on our radar screen, Leaver said.

Evidence of large numbers of undocumented workers leaving the state is anecdotal at this point, although activists say that is happening in Hispanic communities, particularly in Tulsa, where sheriff's deputies have been trained to assist immigration authorities under a federal program.

Statewide figures from the Department of Education on enrollment of Hispanics are not yet available. A drop in enrollment could be an indication of people leaving the state or keeping their children out of school.

Under federal law, all children are required to attend school, regardless of their citizenship status.

Schools in Guymon, which has a high concentration of Hispanics, have reported a 2 1/2 percent increase in Hispanic students, based on enrollments as of Oct. 1.

Statewide enrollment figures will be based on a similar time period and may not capture any late exodus of students from the system.

Federal law requires that hospitals provide emergency care for undocumented workers or anyone else and the new law will not change that, said Joe Kilgore spokeswoman for the Health Care Authority.