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Story highlights

"You have to be kidding me?!" Trump Jr. tweeted

Khan and Trump had sharp words for each other during the campaign

Editor’s Note: This story has been updated to reflect the latest number of fatalities from London Metropolitan Police.

(CNN) —  

President Trump’s son is criticizing the mayor of London in the immediate aftermath of an attack in the city that killed four and wounded about 40 on the grounds of the UK Parliament.

Trump’s son, Donald Trump Jr., manages the Trump Organization and has no role in the White House, but he remains an occasional surrogate for his father. The younger Trump also occasionally calls out the President’s political opponents on Twitter, the venue he chose Wednesday to weigh in on the incident in Britain.

“You have to be kidding me?!” Trump Jr. tweeted, as he shared an article from The Independent, and paraphrased its headline as: “Terror attacks are part of living in big city, says London Mayor Sadiq Khan”

The article, published in September 2016, featured Khan’s reaction to a bombing in the Chelsea neighborhood of New York. In it, Khan said that preparedness for terror attacks is “part and parcel of living in a big city,” and asked Londoners to be correspondingly “vigilant.”

Twitter reacts

Twitter users took to the platform to criticize Trump for his take on the tragedy.

Labour politician Wes Streeting – a party colleague of Khan – called the President’s son a “disgrace” for capitalizing on the attack for “political gain.”

“You use a terrorist attack on our city to attack London’s Mayor for your own political gain,” he wrote. “You’re a disgrace.”

A journalist for UK broadcaster Channel 4 accused Trump of mischaracterizing Khan’s words – suggesting that he didn’t read past the article’s lead paragraph.

“Is this helpful @DonaldJTrumpJr?” Ciaran Jenkins wrote. “Did you even read the article before goading London’s Mayor during a live incident?”

Condolences

The White House issued a more conciliatory response to the terrorist attack. The President spoke by phone with British Prime Minister Theresa May, and White House press secretary Sean Spicer said it would be “irresponsible” to speculate this soon on what precisely happened or who was responsible.

Khan and Trump Sr. had sharp words for one another during the campaign: Khan, who is Muslim, criticized Trump’s immigration ban, and Trump at one point challenged the London mayor to an I.Q. test.

Editor’s note: This story has been updated to reflect the latest number of fatalities from London Metropolitan Police.