CLEVELAND (CBS) — President Donald Trump brought up shootings in Chicago as he attacked Democratic rival Joe Biden on the issue of law and order in the first 2020 presidential debate Tuesday night.

Moderator Chris Wallace of Fox News – a former CBS 2 reporter – asked a question about the rise in homicides in America and President Trump laying the blame on Democratic governors and mayors. Wallace noted that there have been equivalent spikes in Republican-led cities such as Tulsa and Fort Worth.

President Trump replied, “I think it’s a party issue.” He then quickly launched into his often-repeated talking point about Chicago gun violence.

“If you look at Chicago, what’s going on in Chicago, where 53 people were shot and eight died,” President Trump said. Those figures do reflect the gun violence numbers reported by Chicago Police this past weekend.

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He also mentioned New York City, where he claimed violent crime had risen “150, 200 percent.”

“It’s crazy what’s going on, and he doesn’t want to say ‘law and order,’ and he can’t, because he’ll lose his radical left supporters, and then it’s all over,” President Trump said of Biden.

Mr. Trump went on to say if Biden were elected, “the suburbs would be gone.”

Biden replied, “You wouldn’t know a suburb unless you took a wrong turn,” and, “this is not 1950.” The former vice president noted that he himself grew up in the suburbs, and in the present day, the suburbs are places where people drive kids of multiple races and ethnicities to soccer practices all together in one car.

Biden also said he is opposed to calls for defunding police departments, and said President Trump had actually accomplished such a thing himself by cutting federal budgets to law enforcement.

Violence in Chicago was also trending on social media during the debate, CBS 2’s Chris Tye reported. After 9 p.m., Chicago became the focal point of social media chatter, and it was a challenge to find tweets about Chicago that were suitable for TV, Tye reported.

But one such tweet was from Mayor Lori Lightfoot herself, who was quick to take President Trump to task.

“.@realDonaldTrump, keep “Chicago” out of your lying mouth,” the mayor tweeted.

Subsequently, the mayor issued a thread of tweets denouncing President Trump and praising former Vice President Biden.

University of Chicago doctoral student Matthew Borus wrote on Twitter: “I live in Chicago, and I have to ask…if Trump really thought it was so lawless and dangerous, why does he have one of his signature towers here? He even opened it during Obama’s presidency!”

And Rachael Leek tweeted: “Say Chicago one more time. SAY CHICAGO ONE MORE TIME.”

Chicago was not the only city that was talked about when it comes to urban violence on social media during the debate. With regard to hashtags referencing U.S. cities, Portland got 51 percent, Chicago 40 percent, Minneapolis 5 percent, and Kenosha 4 percent, Tye reported.

CBS 2’s Chris Tye contributed to this report.