Donald Trump Jr. in February in Vancouver, Canada. —Jeff Vinnick / Getty Images

It has become something of an online custom in the social media age to react to tragic news stories — like Wednesday’s terror attack in London — with well-meaning if sometimes rote messages like “thoughts and prayers.” But that does not appear to be Donald Trump Jr.’s style.

“You have to be kidding me?!” Trump tweeted on Wednesday afternoon, as details of the attack — which left at least four dead and 20 injured — and its toll continued to unfold. “Terror attacks are part of living in big city, says London Mayor Sadiq Khan.”

Trump, the oldest son of President Donald Trump, used his tweet to call attention to an article from last September in The Independent, a British newspaper, that described Khan’s reaction to the bombing in New York City’s Chelsea neighborhood.

You have to be kidding me?!: Terror attacks are part of living in big city, says London Mayor Sadiq Khan https://t.co/uSm2pwRTjO — Donald Trump Jr. (@DonaldJTrumpJr) March 22, 2017


The younger Trump badly mischaracterized the London mayor’s remarks. Khan did not describe terrorism as “part of living in a big city,” as if bombings and shootings were an inescapable fact of life. He said that terrorism preparedness, including providing sufficient support to the police, was “part and parcel of living in a great global city.”

“That means being vigilant, having a police force that is in touch with communities; it means the security services being ready, but it also means exchanging ideas and best practice,” Khan said in a video interview published by The Evening Standard, another British paper. (For the record, Khan did say the victims of the Chelsea bombing were in his “thoughts and prayers.”)

“Nothing is more important to me than keeping Londoners safe,” Khan added. “I want to be reassured that every single agency and individual involved in protecting our city has the resources and expertise they need to respond in the event that London is attacked.”

Trump’s tweet was not well received by Britons, who were still learning details of the attack when the son of the president of the United States decided to weigh in. On Twitter, Wes Streeting, a member of Parliament from the Labour Party, accused Trump of capitalizing on the attack in London and called him “a disgrace.”

@DonaldJTrumpJr You use a terrorist attack on our city to attack London's Mayor for your own political gain. You're a disgrace. — Wes Streeting MP (@wesstreeting) March 22, 2017


Ciaran Jenkins, a correspondent for Britain’s Channel 4, asked Trump on Twitter if he thought his remarks were “helpful.”

“Did you even read the article before goading London’s Mayor during a live incident?” he wrote on Twitter. He added, “Headline is based on very first sentence, which if you’d bothered to read it could apply to any major city in the world. Key word: ‘threat.’”

Is this helpful @DonaldJTrumpJr? Did you even read the article before goading London's Mayor during a live incident?https://t.co/Sm68UOcJQG — Ciaran Jenkins (@C4Ciaran) March 22, 2017

Trump declined to elaborate on his tweet later on Wednesday. “I’m not going to comment on every tweet I send,” he said in an email.

Political violence in the United Kingdom is relatively rare, but the country has not been immune to terrorism. The country endured decades of sectarian violence in Northern Ireland that often spilled over into Britain, but there has not been a large-scale attack since July 7, 2005, when jihadis killed more than 50 people in attacks on subway trains and a bus.

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Eric Lipton contributed reporting.