WATCH: Mayor Lori Lightfoot's full remarks after shutting down lakefront
Lightfoot said crowds of 100 people or more were reported along the city's lakefront Wednesday, prompting her to issue the executive order to help stem the spread of COVID-19.
"Congregating on our lakefront, to be blunt, is going to create a risk that is unacceptable and could lead to death," Lightfoot said. "Dear God, stay home, save lives. More people will die if we don't abide by this simple, but important order."
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Playgrounds are closed and now the city is also banning contact sports, including basketball games.
"We've had repeated reports of people engaging in full contact sports as if this virus isn't serious," Lightfoot said. "A pandemic means it's here in our midst every day, and we've got to all do our part."
Her drastic action came as Illinois reported 673 new cases of COVID-19 - more than double since Wednesday - bringing the total number of cases in Illinois to 2,538. Seven more deaths were announced as well, bringing Illinois' death toll to 26.
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"Without question, your continued failure to abide by these life-saving orders will erase any progress that we have made over the past week in slowing the spread of this disease, and could lead to more deaths," Lightfoot said.
Lightfoot said cooperation from every resident is critical as new data indicates the city could see more than 40,000 hospitalizations from COVID-19 disease in the coming weeks.
"What we saw yesterday at the lake, from what we saw yesterday at the Bloomingdale Trail, the 606 - that is a very real and direct threat to the health and well-being of everyone in the city," said Chicago Park District Supt. Michael Kelly. "It has to stop."
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Chicago police have been stationed at parks throughout the city ready to break up and ticket any large gatherings. Interim Chicago Police Supt. Charlie Beck said his officers broke up dozens of groups Wednesday with one arrest.
"This is serious business," Beck said. "This is not a game. This is not a time to think about your own physical strength and conditioning over public health."
The mayor was joined by other mayors from nearby villages standing in solidarity with her message, one she says will she will continue to stand by.
"When it comes to staying home and being responsible most Chicagoans have been doing their part, but many have not and you know who you are," Lightfoot said.
On Wednesday, Mayor Lori Lightfoot threatened a crackdown on those who continue to violate the state's 'stay-at-home' order issued by Governor JB Pritzker last week.
The order took effect over the weekend, but warmer weather seemed to bring more people outside Wednesday, including some ignoring the social distancing rules.
Groups of people were seen playing basketball and soccer, which both involve physical contact; dog and their owners packed onto Chicago's dog beach, and others took advantage of the nice weather with picnics along the lakefront. All are activities the city says is unacceptable.
Chicago police began clearing people from the lakefront Wednesday night in an effort to enforce the stay-at-home order.
Mayor Lori Lightfoot made it clear that if people continue to push the limits of the order, lakefront closures could become much more frequent to enforce social distancing.
"Way too many people gathering like it's just another day. This is not just another day, and no day will be just another day until we're on the other side of the virus, which is weeks away," Lightfoot said.
The mayor reminded residents that you are allowed to leave your home to buy food and other essentials, and if you're going on a walk it should be near your home. She also emphasized that you must remain six feet from other people.
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"You have to stay at home as much as possible," Lightfoot said.
Officials said those who continually flout these restrictions could be issued a warning or a citation, and possible a $500 fine and even arrest for repeat offenders.
"We're going to give you an admonition and if you don't turn right away and head home, then you're going to get a citation," said Lightfoot. "And if worse, yeah, we will take you into custody."
"Because if we do not do this, Chicago is at risk," said Interim CPD Superintendent Charlie Beck. "Your families are at risk. The seniors in this city are at risk."
"If people don't take this in a serious way in which they must, I'm not going to hesitate to pull every lever at my disposal to force compliance if necessary," Lightfoot added.
Sun-Times Media Wire contributed to this article