A Trump Organization executive that prosecutors have been trying to flip will testify for a grand jury investigation into the company

Matthew Calamari Jr., who serves as the Trump Organization's corporate director of security and is the son of the company's chief operating officer, is expected to testify in front of a grand jury this week as part of the Manhattan District Attorney's investigation into the company's finances.

Calamari Jr. was served a subpoena for his testimony, his attorney told Insider. Prosecutors have long sought the cooperation of Calamari Jr. and his father, Matthew Calamari, who has worked for the Trump Organization for decades. The Wall Street Journal first reported on the subpoena.

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