FILE PHOTO: US Secretary of the Interior Ryan Zinke arrives at the US Capitol prior to the service for former President George H. W. Bush in Washington, DC, USA, 03 December 2018. Shawn Thew/Pool via REUTERS

(Reuters) - U.S. prosecutors have started presenting evidence to a grand jury in Washington to examine whether former Interior Secretary Ryan Zinke lied to federal investigators, the Washington Post reported on Friday, citing two people familiar with the matter.

The Post said the deliberations were focused on Zinke’s refusal to grant a petition by two Native American tribes, the Mashantucket Pequot and Mohegan, to operate a commercial casino in East Windsor, Connecticut.

In response to the tribes’ efforts, competing casino operator MGM Resorts International, which opposed the planned casino, launched a lobbying campaign, The Post said.

The tribes alleged that Zinke refused the petition under political pressure. The Interior Department’s inspector general’s office conducted an investigation during which it came to believe that Zinke lied in the course of the inquiry.

The Department Of Justice did not immediately respond to a request for comment and Reuters could not reach Zinke.

Zinke stepped down as interior secretary at the end of 2018. There was no reason given for his departure when it was announced in mid-December, but he had faced scrutiny into his use of security details, chartered flights and a real estate deal in his home state of Montana.