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A Republican lawmaker is calling for a hearing into border security following the murder of a prominent Arizona rancher by an assailant authorities believe was an illegal immigrant.

Rep. Kay Granger of Texas, the top Republican on the House Foreign Operations subcommittee, told Fox News on Thursday that she would like to have a hearing as soon as Congress returns from its Easter recess to help border states whose pleas for federal assistance have so far gone unmet.

"I don't think that we are getting everything we need," she said, adding that the hearing would provide a platform to discuss what is needed.

Granger said the border fence that was under construction in the Southwest was not helpful.

"What we need is sensors, we need more equipment to see who's coming across the border," she said. "We need more roads so that border control can stop them. We need more commitment frankly. We need commitment to make sure that our borders are safe and they're not right now with what's going on in Mexico."

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Late Saturday, Robert Krentz, a 58-year-old rancher whose family has lived there for a century, was found slumped over his ATV on his ranch. Footprints led back across the Mexican border, and local police say an illegal immigrant probably killed him.

A satellite photo from U.S. Customs and Border Protection shows a gap in the border fence near Krentz's ranch in southeastern Arizona.

Meanwhile, border states are taking matters into their own hands, boosting law enforcement to patrol for illegal immigrants. New Mexico Gov. Bill Richardson is sending his state's National Guard troops to the border it shares with Mexico.

"I believe we need a permanent presence," Richardson told Fox News on Thursday. "More border patrol, more National Guard at the border, the guard doing basically secondary work to the border patrol, mainly technical, because the border violence is now related to drugs, to cartels fighting each other, to violence affecting Americans like that one that was killed."

Gov. Jan Brewer told Fox News on Wednesday that after repeatedly calling on the federal government to send in 250 National Guard troops, she hasn't ruled out making the call herself.

But Brewer stressed that Arizona cannot afford to sustain or maintain the additional National Guard presence. She said border security is a federal responsibility -- and she said the administration simply is not stepping up.

Matthew Chandler, spokesman for the Department of Homeland Security, told FoxNews.com in a written statement that the department "will respond directly to the members of Congress" who are making the requests.

Homeland Security Secretary Janet Napolitano, formerly the governor of Arizona, "shares these members' concern about the safety of U.S. border communities and is committed to working with our state, local, tribal, and Mexican law enforcement partners to combat threats from violent cartels on both sides of the border," he said.