Desert heat kills 12 in Arizona

YUMA, Arizona -- Twelve men died Wednesday of heat exposure in a rugged, sweltering area of Arizona wilderness along the U.S.-Mexican border. The U.S. Border Patrol said a search was under way for four other missing men.

"Border Patrol apprehended several individuals who stated they had been part of a larger group who had been smuggled across the border," Border Patrol spokeswoman Karen Kraushaar said. "They're trying to determine where the rest are."

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Another 11 had been taken to a hospital late Wednesday, she said.

The 12 died of heat exposure and lack of water, officials said.

The group, all of them Mexican nationals, was found in the mountainous San Cristobal Valley on Wednesday afternoon, she said. Survivors gave agents "a pretty good idea" of where the others might have gone, she added.

Kraushaar said this type of smuggling is happening with increasing frequency. Smugglers lure people to trust them, then promise to take them across the border for a fee.

The smugglers promise safety will be just a short walk from the drop-off point, when in fact the immigrants are dropped off in the wilderness to face treacherous conditions, Kraushaar said.

Temperatures in Yuma reached a high Wednesday of 109 degrees Fahrenheit (43 Celsius), the National Weather Service said.