The NBA released a statement on Thursday evening saying that David Stern, NBA Commissioner Emeritus, "suffered a sudden brain hemorrhage earlier (Thursday) for which he underwent emergency surgery."
"Our thoughts and prayers are with David and his family," the statement concluded.
ESPN's Adrian Wojnarowski has reported that Stern collapsed while at Brasserie 8 1/2 in Manhattan and was then rushed to the hospital for surgery.
Stern, 77, served as NBA Commissioner from February 1, 1984 until January 31, 2014, when he was succeeded by current league Commissioner Adam Silver.
During his tenure, Stern oversaw the league create seven new franchises, while six teams relocated during his years as Commissioner. He also instituted a league dress code that remains in place to this day. He is also the founder of the WNBA.
Stern was inducted into the Naismith Memorial Basketball Hall of Fame in 2014.