Three died at the nursing home, and three others died after being evacuated to Memorial Healthcare System facilities, city officials said.
"This is the most stressful situation I've lived in my life", Alvarez said.
Dr. Jack Michel, a physician who serves as the president of Larkin Community Hospital in South Miami, was involved a massive fraud scheme at Larkin more than a decade ago, according to the U.S. Department of Justice.
The Rehabilitation Center at Hollywood Hills has a health inspection rating of "much below average" by the Florida Agency for Healthcare Administration, which evaluates all long-term care facilities in the state for the US government.
South Carolina Gov. Henry McMaster on Tuesday lifted the state's last evacuation order, which had been in effect on the barrier islands in the southern part of the state.More news: US Supreme Court Gives Green Signal to Trump's Travel Ban on Refugee
The nursing home's licensee is Rehabilitation Center at Hollywood Hills, LLC, which is owned by a doctor named Jack Michel. He also said investigators will look into how many windows were open in the nursing home.
In both cases nursing home administrators said they would rectify the problems.
The nursing home has had a list of safety violations and citations, including two for not following generator regulations in 2014 and 2016.
Florida governor Rick Scott said the state's top priorities are getting fuel delivered to gas stations and turning the power back on for those affected.
"We need to make sure we're doing everything we can to keep our seniors safe during this hard time", he said. Police say three patients died at the facility and three at a hospital.
Carbon monoxide from a generator is also suspected in the death of a man in Miami, while authorities say another dozen people were treated for carbon monoxide-related illnesses on Tuesday in Polk and Brevard counties.
Meanwhile, one of the main highways that connects Florida to the rest of the country is in danger of being closed due to flooding caused by Hurricane Irma.
Sharief said as far as power restoration goes, as of Wednesday morning 34 percent of the county remains without power. "I don't know if she is dead or alive", Ms. Mitchell said.