Mashantucket — Foxwoods Resort Casino staff and the Mashantucket Pequot Tribe mourned the loss Monday of Felix Rappaport, the casino's president and chief executive officer, who was found dead Monday morning in his casino hotel room. He was 65.

Mashantucket Pequot tribal police determined the death was not suspicious, said Lori Potter, a spokeswoman for the tribe, which owns the casino.

"A cause of death has not been determined," Foxwoods said in a news release it emailed shortly before 3 p.m.

No autopsy is planned, Potter said.

"On behalf of the entire Tribal Council, Foxwoods management team and staff, we extend our deepest sympathies to Felix's family," Rodney Butler, the Mashantucket chairman, said in a statement. "With his passing, we have suffered a major loss. Felix's passion for modernizing and growing Foxwoods, as well as his friendship, mentorship and humor touched everyone who worked with him. We are confident that Felix's legacy will live on as we continue to push forward on the vision he set."

Rappaport arrived at Foxwoods in February 2014 following a long career at casinos in Las Vegas. Named senior vice president and chief operating officer, he was elevated to president and chief executive officer nine months later, succeeding Scott Butera.

“I’m tremendously saddened by his passing,” Butera said by phone Monday evening. “He was an outstanding individual, personally and professionally. One of my happiest days at Foxwoods was when he agreed to join our team. He’ll be sorely missed.”

Rappaport's death stunned people throughout the industry.

"It's totally shocking," said Mitchell Etess, a senior adviser to the Mohegan Tribe, which owns Mohegan Sun, Foxwoods' chief rival. "I've been working with him very closely on the East Windsor project and had gotten to know him. He was a really great and unique person — and personality. Obviously, he had been doing a wonderful job at Foxwoods."

The Mashantucket and Mohegan tribes are collaborating on a commercial casino project in East Windsor.

"It's a terrible loss for many people on many levels," Etess said.

Rappaport attended the 22nd annual East Coast Gaming Congress last week in Atlantic City, participating Thursday in the two-day conference's signature event, a roundtable discussion among gaming-industry CEOs.

"We are all shocked and saddened by his passing. He's widely regarded as one of the good guys in gaming," said Joe Weinert, executive vice president of Spectrum Gaming Group, one of the conference's organizers.

Born in California and raised in Philadelphia, Rappaport graduated from the University of Pennsylvania and took a job with the American Red Cross. Later, he went to work in gaming and hospitality in Atlantic City and Pennsylvania, and in 1991 moved to Las Vegas, where he became vice president of hotel operations for The Mirage.

He went on to become executive vice president of MGM Grand and president of such casinos as New York-New York, Luxor, Excalibur and The Mirage, which he left at the end of 2012.

Long recognized as an innovator, Rappaport sought to diversify Foxwoods' offerings in a bid to lessen its dependence on gaming revenues. He introduced Las Vegas-style entertainment to Foxwoods' mix, and oversaw the opening of the Tanger Outlets at Foxwoods and, more recently, such attractions as "thrill" rides and a zip line.

"In addition to a focus on enhanced service and quality, he was a true believer in making Foxwoods a fun and engaging place to work for all its 6,500-plus team members," Foxwoods said.

b.hallenbeck@theday.com