Dmitry Sivenkov, 32, from Russia; Gillhem Bellon, 25, of France; and Luca Ogliengo, 25, from Italy began their ascent of the active Villarico volcano in central Chile early last week, Russia's RIA Novosti news agency reported.
The trio was last heard from Wednesday night when one of the hikers called his girlfriend to say they were spending the night on the rugged mountain.
Ground searchers said Friday they had found the path the hikers used for the ascent, but there was no sign of an encampment.
The family of the missing Italian man has hired a private helicopter to join the search, the report said.
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