Alexander Korshunov, 57, the head of business development at the state conglomerate Rostec’s subsidiary United Engine Corporation, was reportedly detained Tuesday as he arrived in Naples from Moscow. He is accused of embezzling intellectual property and General Electric documents for a Russian aircraft engine program, the Vedomosti business daily reported .

An executive with Russia’s state engine maker has been arrested in Italy at the request of the U.S., which suspects him of economic espionage, the Fontanka.ru news website reported Thursday.

Italian police had presented Korshunov with a U.S.-issued arrest warrant, Fontanka.ru reported.

“He’s been accused of stealing some secrets,” President Vladimir Putin said at an economic forum in Far East Russia on Thursday, adding that the arrest looked like it was motivated by what he called unfair competition.

Putin said UEC had developed a new Russian engine and concluded a contract with an Italian consulting firm.

“It’s open commercial work, a global practice. Now the American partners claim that something was stolen,” Putin said.

The RBC news website cited a UEC source as saying that Korshunov was arrested last Friday. An Italian court was set to consider Korshunov’s extradition to the U.S. on Thursday, the Vedomosti business daily cited an unnamed source as saying.

Russian diplomats demanded the U.S. State Department to withdraw its extradition request for Korshunov, Russia’s Embassy in Washington said in a statement.

The “vicious practice of the U.S. authorities in hunting down Russian citizens all around the world” further erodes and causes “unpredictability” in Russian-American relations, the embassy said around midnight Friday.

Italy's foreign ministry said it had no immediate comment to make on the case.

UEC produces engines for civil and military aircraft as well as power turbines. Russian state conglomerate Rostec, which owns the engine maker, said Korshunov was innocent of any wrongdoing as did UEC, Russian news agencies reported.

Reuters contributed reporting to this article.