LINK By CHARLES HURT in D.C. and CARL CAMPANILE in N.Y. August 22, 2007 -- The Big Apple came under harsh attack yesterday from Republican White House hopefuls hunting for votes. Mitt Romney launched a radio ad in New Hampshire and Iowa blasting New York as a "sanctuary" for illegal immigrants - a zinger aimed at front-runner rival Rudy Giuliani. Hours later, Fred Thompson came out with both barrels blazing - hitting Giuliani and Mayor Bloomberg over their Gun-control policies. Illegal immigration and gun control are potent issues among Republican primary voters. "Immigration laws don't work if they're ignored," the narrator in the 1-minute Romney radio spot says. "That's the problem with cities like Newark, San Francisco and New York City that adopt sanctuary policies. "Sanctuary cities become magnets that encourage illegal immigration and undermine secure borders." Former Mayor Ed Koch initiated the policy in the 1988 to encourage illegal immigrants to report crimes, seek medical treatment and enroll their kids in schools without fear of being reported. The policy was continued by successors David Dinkins, Giuliani and Bloomberg. A Giuliani campaign official said Romney's slam was "desperate" and "hypocritical." "Governor Romney's ad conveniently forgets that his trooper plan never took effect and he did absolutely nothing to cut down on the number of illegals working in his yard," the Giuliani insider said, referring to illegal immigrants discovered mowing the former Massachusetts governor's lawn. Bloomberg dismissed Romney's charge, saying, "We welcome immigrants, we want more of them." Meanwhile, Thompson said he spent time in the city while starring as DA Arthur Branch on TV's "Law & Order." "There are a lot of things about the place I like, but New York gun laws don't fall in that category," the still-undeclared candidate wrote on his blog. "Unfortunately, New York is trying . . . to force its ways on the rest of us, this time through the courts," Thompson wrote, referring to a Brooklyn judge's ruling allowing the city to sue certain out-of-state gun dealers. "We need federalism to protect states from a big bully in New York City." Bloomberg spokesman Stu Loeser returned fire: "We like the tough-on-crime fictional prosecutor better than the pandering nonfictional candidate."