This is part of the America's Future series airing on FOX News Channel, looking at the challenges facing the country in the 21st century.

LOS ANGELES — With gang violence on the rise in Los Angeles, the city's mayor is criticizing the Department of Homeland Security for what he says are its misguided priorities on immigration enforcement.

Recent raids on LA area businesses by Immigration and Customs Enforcement agents have resulted in the arrest of hundreds of illegal workers. But Mayor Antonio Villaraigosa says ICE is using scarce funds to target “non-exploitative" businesses, and that the agents should be rounding up illegal alien gang members instead.

"At a time when ICE has said that they don't have the resources to go after those undocumented who are committing serious felonies, but do have the resources to go after legitimate employers, what I'm saying is, we need to prioritize our resources," Villaraigosa said.

Prior to last month, ICE had made more than 3,700 arrests in connection with worksite enforcement investigations, including 850 involving criminal violations.

The mayor said the raids target people who make a positive contribution to the community, and they ignore violent criminals.

But critics say Villaraigosa supports a controversial policy that prevents cops from enforcing immigration policy.

Special Order 40 is a 30-year-old Los Angeles Police Department ordinance that prevents cops from stopping suspects solely on the suspicion that they are illegal immigrants. The procedure also bars LAPD officers from cooperating with federal immigration agents.

Rick Oltman, spokesman for the immigration advocacy group Californians for Population Stabilization, said the mayor can't have it both ways.

"The mayor wants his police not to be involved in immigration enforcement, yet he wants to harangue the federal government for coming after the criminal aliens in his town which he has virtually set up as a sanctuary city. There's just a little bit of double talk going on here," said Oltman.

It's a familiar battle that is playing out in cities across the country. Police say they want illegals to be willing to talk to them and provide information to help fight crime. But illegals, fearing deportation and other charges, are afraid to come forward.

In a recent press conference Villaraigosa reiterated his support for Order 40, saying it is critical to help fight crime.

"We believe that the city is safer when our police department is collaborating and cooperating with witnesses and victims who happen to be undocumented, that our city and our neighborhoods are safer when they feel that they can cooperate with the police."

But critics like Oltman think the mayor's opposition to workplace raids is more political in nature.

"He doesn't want to disrupt the flow of cheap labor to businesses who have been benefiting from this all along, so it's the classic double speak: say one thing to one group, say something to another group," said Oltman.

Click here to read more from FOX News' America's Future.