Facing criticism for tweeting a day earlier that Rep. Elijah E. Cummings’s Baltimore district is a “rodent infested mess” where “no human being would want to live,” President Trump tweeted Sunday that the Democratic congressman is “racist” and that “his radical ‘oversight’ is a joke!”

In a tweet after returning to the White House from his Virginia golf club late Sunday afternoon, Trump said there was “nothing racist” about “stating plainly what most people already know.”

Cummings, he added, “has done a terrible job for the people of his district, and of Baltimore itself. Dems always play the race card when they are unable to win with facts. Shame!”

As chairman of the House Oversight and Reform Committee, Cummings has initiated most of the investigations of the Trump administration’s operations and policies, including of reports of inhumane treatment at migrant detention centers.

Acting White House chief of staff Mick Mulvaney on Sunday defended Trump’s attacks on Baltimore and Cummings, saying that some people will be offended by anything the president says.

“Do you understand that that is offensive to the Americans who do live there?” host Margaret Brennan asked on CBS News’s “Face the Nation.”

“I understand that everything that Donald Trump says is offensive to some people,” Mulvaney replied.

Brennan continued to press him, repeating Trump’s statement that “no people would want to live there.”

“This is being perceived as racist. Do you understand why?” she asked.

“I understand why, but that doesn’t mean that it’s racist,” Mulvaney responded. “The president is pushing back against what he sees as wrong. It’s how he’s done it in the past, and he’ll continue to do it in the future.”

Mulvaney added that Trump’s point was that congressional Democrats are “focusing on scandal in Washington, D.C.,” instead of helping residents of their districts.

On “Fox News Sunday,” Mulvaney argued that it was “fair to have that conversation” about the conditions in Cummings’s district.

“Have you seen some of the pictures on the Internet, just this morning, of the conditions in Baltimore, Maryland? . . . The richest state in the nation has abject poverty like that — a state, by the way, dominated for generations by Democrats,” Mulvaney said.

Before entering the Trump administration in 2017, Mulvaney represented South Carolina’s 5th Congressional District. The district had a median income of $44,685 in 2018 — lower than the $56,350 median income of Maryland’s 7th Congressional District, which Cummings represents.

Cummings responded to Trump’s initial attacks on Saturday, defending his dedication to his constituents.

“Mr. President, I go home to my district daily. Each morning, I wake up, and I go and fight for my neighbors,” he tweeted. “It is my constitutional duty to conduct oversight of the Executive Branch. But, it is my moral duty to fight for my constituents.”

The episode marks the second time in two weeks that Trump’s statements about a minority lawmaker have sparked outrage. Earlier this month, he tweeted that four minority congresswomen should “go back and help fix the totally broken and crime infested places from which they came.” Days later, after Trump criticized one of the women, Rep. Ilhan Omar (D-Minn.), a crowd at a rally in North Carolina responded by chanting, “Send her back! Send her back!”

All four of the congresswomen are U.S. citizens. Three of the four were born in the United States; Omar was born in Somalia and became a U.S. citizen as a teenager.

In defending himself Sunday, Trump shared a post by Katie Hopkins, a far-right British commentator whom the president retweeted earlier this month. Hopkins is known for her incendiary commentary, including a 2015 column in which she compared migrants to “cockroaches” and “feral humans.”

In the post Trump retweeted Sunday, Hopkins referred to Baltimore as a “proper sh*thole.” Trump himself reportedly has used the word “shithole” to describe certain African and Latin American countries. He has denied making the comment.

Some on Sunday said that Trump’s attacks on minority lawmakers have gone too far. Julián Castro, a former mayor of San Antonio and a housing secretary in the Obama administration, said it is “absolutely” important to call out Trump’s rhetoric for what it is, “which is racism.”

“Like a lot of Americans, I’m not somebody that likes to use that term or that is quick to call somebody a racist,” Castro, who is running for president, said on “Face the Nation.” But “there is a pattern here,” he added.

“This guy is the biggest identity politician that we have seen in the last 50 years, and he engages in what’s known as racial priming — basically using this language and taking actions to try and get people to move into their camps by racial and ethnic identity,” Castro said. “That’s how he thinks he won in 2016, and that’s how he thinks he’s going to win in 2020.”

Sen. Chris Murphy (D-Conn.) announced Sunday morning that he has had enough of the president’s rhetoric and is unfollowing him on Twitter.

“I’m unfollowing the President of the United States today on Twitter, because his feed is the most hate-filled, racist, and demeaning of the 200+ I follow, and it regularly ruins my day to read it. So I’m just going to stop,” Murphy tweeted, adding: “I can’t believe I just typed that.”

Congressional Republicans, meanwhile, declined to criticize Trump for his attacks on Cummings.

Sen. Rick Scott (Fla.) repeatedly avoided stating his opinions about the tweets on NBC News’s “Meet the Press,” pivoting away from questions about Trump and racism and toward Cummings’s statements about Border Patrol agents — excoriating the congressman for those remarks while reserving judgment for the president.

“I didn’t do the tweets, Chuck. I can’t talk about why he did what he did, but I’m very disappointed in people like Congressman Cummings, who is attacking Border Patrol agents that are trying to do their job when the Democrats won’t give them the resources to do it,” Scott told host Chuck Todd.

Rep. Will Hurd (Tex.), the only black Republican in the House, said he personally wouldn’t have tweeted what Trump did about Cummings’s district. But he said those tweets were different from the president’s earlier tweets telling the congresswomen to “go back.”

Hurd had been among the most vocal critics of those remarks and was one of only four Republicans who voted for a resolution condemning them.

“Chairman Cummings is someone I worked with closely on all kinds of legislation,” Hurd said on ABC’s “This Week”. “He is someone that cares passionately about his community and has been working tirelessly his entire adult life on behalf of his country and his community and he is someone — he can defend himself.”

Karoun Demirjian and Colby Itkowitz contributed to this report.