New York prosecutors are investigating whether a top Trump Organization executive, Matthew Calamari, received tax-free fringe benefits, as part of their probe into whether former President Donald Trump’s company and its employees illegally avoided paying taxes on such perks, according to people familiar with the matter.

Prosecutors’ interest in Mr. Calamari, once Mr. Trump’s bodyguard, indicates that their probe into the Trump Organization’s alleged practice of providing some employees with cars and apartments extends beyond Allen Weisselberg, the company’s chief financial officer, and his family. Neither Messrs. Calamari and Weisselberg, nor anyone else connected to the company, has been accused of wrongdoing.