MEXICO CITY—As Covid-19 cases and deaths mount across Mexico, the country’s second richest businessman is publicly defying health recommendations meant to prevent the spread of the new coronavirus, sparking a confrontation with the government.

Ricardo Salinas Pliego, who controls an empire of retail, banking, broadcasting and other businesses worth more than $10 billion, has criticized government attempts to slow the virus by ordering nonessential businesses closed and imposing social-distancing measures.

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