PHOENIX – Sheriff Joe Arpaio announced Thursday that his deputies will begin placing white crosses near the sites where authorities find bodies of immigrants who are dying in the desert after crossing the border from Mexico.

The sheriff stood amid about a dozen crosses to announce an effort that he said would serve as a reminder of just how dangerous the journey is from Mexico through the rugged desert of southern Arizona.

He said four bodies have been found in the last four days near Gila Bend after succumbing to the scorching desert heat. Two others were rescued this week.

Each cross also will be numbered and assigned GPS coordinates to aid his deputies in rescuing people who find themselves in distress in the area and can call for help, the sheriff said.

"If we have to do 1,000 of these, or 5,000, we'll do it," said Arpaio, who became a prominent national figure in the immigration debate in recent years.

Arpaio's county does not run along the border, but some areas of his jurisdiction are heavily trafficked smuggling routes.

The U.S. Border Patrol's Tucson sector located 177 bodies in the last fiscal year. Immigrants frequently walk up to a week in debilitating heat, often with enough bottled water and canned tuna to last only days.

Arpaio, who has been a vocal critic of President Barack Obama's border security efforts, also wants the federal government to pay the costs his office incurs for body recoveries and rescues.