Businessman Alejandro Burzaco, one of three Argentines wanted by U.S. authorities over the FIFA bribery investigation, surrendered voluntarily to police in northern Italy on Tuesday.
Italian police said Burzaco turned himself in to authorities in the city of Bolzano, but they provided no further details.
Separately, an Italian regional police official told Argentine radio station La Red that Burzaco showed up unannounced at a police station accompanied by two lawyers, one Italian and one Argentine.
"He just appeared all of a sudden," the official said.
U.S. prosecutors say Burzaco, 50, along with Argentines Hugo Jinkis, 70, and his son Mariano Jinkis, 40, conspired to win and keep hold of lucrative media rights contracts from regional football federations through payment of bribes. The whereabouts of the father and son are unknown.
The Argentine judge who ordered the three men's arrest on May 28 said at the time that he did not know if they were in the country.
Burzaco was president of Argentine sports marketing firm Torneos y Competencias (Torneos), while Hugo and Mariano Jinkis are controlling principals of Full Play, another sports media and marketing business headquartered in Argentina.