The 66-year-old executive was recovering from shoulder surgery.
An Italian media outlet has reported that Fiat Chrysler Automobiles CEO Sergio Marchionne has been admitted to intensive care at a hospital in Switzerland.
Marchionne, 66, fell ill after shoulder surgery and was replaced over the weekend as CEO of FCA and also Ferrari.
"Il Messaggero, a Rome newspaper, reported Sunday that 'complications arose which compromised the situation, which worsened in recent hours,' according to a Google translation of a story on the newspaper's website," the Detroit Free Press reported.
"The Italian news agency ANSA said he had been admitted to intensive care. The company said Sunday it planned no statement on Marchionne's condition," the newspaper added.
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In a statement on FCA's media site posted Saturday, the group's Chairman, Jon Elkann, wrote that he was "profoundly saddened to learn of Sergio’s state of health."
"It is a situation that was unthinkable until a few hours ago, and one that leaves us all with a real sense of injustice," Elkann said. He was named Ferrari's Chairman on Saturday.
"Over the past 14 years together we have lived through successes and difficulties, internal and external crises, but also unique and unrepeatable moments, both personal and professional," Elkann added.
Details about the specific nature of Marchionne's illness have been lacking, but various media reports have described his condition as grave. He is being attended by his two sons and his partner.
Marchionne is a turnaround specialist who became CEO of Fiat in 2004. He engineered a takeover of bankrupt Chrysler in 2009, following the struggling Detroit automaker's bailout by the US government during the financial crisis.
IPOs of FCA and Ferrari
He later staged a successful IPO of FCA in 2014.
In 2015, after assuming the CEO's role at Ferrari following the departure of longtime head Luca di Montezemelo, he oversaw the spinoff of the luxury brand and its equally successful IPO.
Marchionne also courted General Motors in a fruitless bid to merge the carmakers.
Known for his casual style — he often appeared in a uniform of black sweater and jeans — Marchionne was an outspoken CEO, rarely avoiding chances to call the auto industry out for its wasteful ways. He was a workaholic chief executive who made immense demands of his underlings and until recently was a chainsmoker and copious consumer of coffee.
Marchionne's health wasn't an issue prior to late last month, when he went in for surgery. He was expected to recover quickly and oversee second-quarter earnings from both FCA and Chrysler this week and next, but he evidently took a turn for the worse.
He had planned to retire from FCA in 2019 but stayed on as CEO of Ferrari until 2021.
Over the weekend, Mike Manley was named CEO of FCA; he had been running the Jeep division. Louis Camilleri will assume Marchionne's CEO role at Ferrari.
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