CHICAGO (CBS) — After warning Chicago businesses last week that more strict enforcement of social distancing requirements was coming, city officials said they issued 10 citations to five businesses over the Independence Day weekend — each with a fine of up to $10,000 — and shut down a lakefront cruise operation for “blatantly ignoring the reopening requirements.”

Last week, Mayor Lori Lightfoot and city officials warned they would be cracking down on bars and other businesses that ignored the city’s capacity limits during Phase 4 of the reopening plan, by allowing too many people to gather in one place, going so far as to close down businesses for particularly egregious violations.

On Monday, the city’s Department of Business Affairs and Consumer Protection said, while the vast majority of businesses complied with social distancing rules, BACP investigators, Chicago Police, Fire Department inspectors, and Buildings Department inspectors responded to complaints at bars and restaurants in entertainment districts in River North, Wrigleyville, Lincoln Park, Wicker Park, and others.

In all, the city conducted 49 investigations of complaints over the holiday weekend, and issued a total of 10 citations to five businesses, each with a fine of up to $10,000. The city also shut down Chicago Lakefront Cruises for showing “egregious disregard for the health and safety of their employees and customers by blatantly ignoring the reopening requirements.”

Lightfoot said the tour boat operator had allowed nearly 100 people to cram onto the top deck of one of their vessels.

“That was unbelievably irresponsible, and there’s going to have to be consequences for them. They had no pretense of social distancing,” she said. “It’s just outrageous.”

The mayor said she wouldn’t repeat the words she uttered when she first saw images of the crowd aboard the Chicago Lakefront Cruises boat.

“You can be sure that I let off a few colorful words at the stupidity of this boat, and there will be consequences for them,” she said.

According to the mayor, a Chicago Police Department Marine Unit boat escorted the tour boat back to shore after discovering the violations, and everyone was told to leave the boat.

Chicago Lakefront Cruises did not immediately respond to a request for comment.

Lightfoot said, overall, she believes Chicago businesses got the message that the city is serious about enforcing social distancing requirements.

“I think, by and large, it was a pretty good weekend,” she said.

The mayor reiterated that the city will continue to be aggressive in citing businesses that violate public health restrictions, including shutting them down for severe violations.

“The time of saying pretty please, and won’t you, and trying to educate, that’s over,” she said.

Since the start of Phase 3 of the city’s reopening plan on June 3, officials have conducted 450 investigations into complaints about businesses violating reopening guidelines. BACP has issued 75 warnings or notices, along with 14 citations.

“The City will continue to ensure a cautious and safe reopening through strict enforcement of the phase four guidelines,” a BACP spokesperson stated in an email.