"It is with profound sadness and terrible grief that we confirm that Mayor Edwin M. Lee passed away," a statement from Lee's office said. "Our thoughts and prayers are with his wife Anita, his two daughters, Brianna and Tania, and his family."
Lee, who had been mayor of San Francisco since 2011, died just after 1 a.m. Tuesday at Zuckerberg San Francisco General Hospital. Officials said he had friends, family and colleagues at his side.
Lee died after suffering a heart attack, the San Francisco Chronicle reported
. He collapsed while shopping around 10:30 p.m. Monday at a Safeway grocery store in San Francisco, according to the newspaper.
Lee was a supporter of sanctuary cities and butted heads with President Donald Trump on immigration issues, KPIX-TV reported
Supervisors and other public officials were stunned and saddened by his sudden death. They praised the low-key mustachioed mayor better known as a former civil rights lawyer and longtime city bureaucrat than a flashy politician.
Former Mayor Willie Brown and the late political power broker Rose Pak talked Lee into filling out the rest of Gavin Newsom's term when he was elected California's lieutenant governor in 2010.
"We won based on our political shenanigans and our political skill sets. He got elevated to our mayor-ship under our charter and got re-elected twice," Brown said.
Brown said Lee will be known as the man who "stepped up and made it possible for Silicon Valley to almost re-locate to our city.
London Breed, who served as president of San Francisco's Board of Supervisors, is now the acting mayor.