Renowned actor, writer and director Harold Ramis died early Monday after struggling with an autoimmune disease. He was 69.



Ramis is known for his extensive resume of comedy classics, including “Ghostbusters,” Illinois-based “Groundhog Day," “National Lampoon’s Animal House," “Stripes” and “Caddyshack,” among many others.



Ramis was born in Chicago and moved his family to the North Shore area in the '90s.



According to the Chicago Tribune, Ramis, who suffered from a rare disease involving swelling of blood vessels called autoimmune inflammatory vasculitis, underwent surgery for diverticulitis in 2010. He suffered complications and spent time at the Mayo Clinic and Rehabilitation Institute of Chicago. Ramis relapsed less than two years later, the Tribune reports, and never fully recovered.



The reaction to his death was immediate, from fans to actors.



"Sad to hear my friend Harold Ramis passed away," Billy Crystal tweeted. "A brilliant, funny, actor and director. A wonderful husband and dad. Big loss to us all."



"No no not Harold Ramis," Jon Favreau tweeted. "Worked for him years ago. He was the real deal. Growing up, his work changed my life. He will be missed."



Ramis got his start as head writer and actor for the TV series “Second City Television (SCTV)” and a writer for "Animal House." He pursued a film career that led to directing, writing and starring in dozens of movies that many consider classics.



“It is impossible to overstate the personal and professional influence that Harold Ramis has had on all of us at The Second City," said Andrew Alexander, CEO and executive producer of The Second City. "He was a natural leader, a trusted friend and so generous with his own talent that he made everyone he ever worked with look like a genius. We are devastated to lose him so young, but we were all enriched by the years we did get to partake of his particular brilliance.”

In 2012, Ramis fed rumors of a third "Ghostbusters" movie.



“Well, there’s been a lot of talk about a third Ghostbusters film, which has now become real. It’s… I can say with some certainty that there will be a third movie."