San Francisco Mayor Edwin Lee passed away at 1:11 a.m. on Tuesday at Zuckerberg San Francisco General Hospital -- just hours after appearing at a public event. He was 65 years old. Lee, who reportedly suffered a heart attack, had been the mayor since 2011.

On Tuesday, the York family issued the following statement on behalf of the San Francisco 49ers:

"The citizens of San Francisco and the greater Bay Area have lost a wonderful man and a tremendous leader with the passing of Mayor Lee. Our hearts go out to Anita, Tania, Brianna and his entire family. Ed was a friend that we came to admire deeply for his compassion for others and his tireless work to effect positive change in both his city and throughout society."

In 2011, Lee replaced Mayor Gavin Newsom, who left to become California's lieutenant governor. He was re-elected as mayor in 2015.

Board of Supervisors President London Breed became the acting mayor following Lee's death.

"Our thoughts and prayers are with his wife Anita, his two daughters, Brianna and Tania, and his entire family," Breed said on Tuesday.