President Donald Trump cited the June 3 terrorist attack in London to make a point about gun control.
In a June 4 tweet, the president wrote that the attack had not provoked a debate on gun control, CNN reported.
"Do you notice we are not having a gun debate right now? That's because they used knives and a truck!" tweeted Trump, according to CNN.
Trump also tweeted his support for Britain following the attack.
Three men drove a white van into pedestrians on London Bridge June 3. They then exited the vehicle and began attacking people with knives.
Seven people died in the attack and at least 48 were injured, according to the BBC. Police shot and killed the three attackers, who were wearing fake bomb vests. CNN reported that the police said they used "unprecedented" force to kill the assailants.
Trump's tweet came shortly after a similar point was made by a Fox News commentator.
"Notice we're not having a gun debate right now, because they didn't kill with guns. They killed with knives. They killed with an ideology," the presenter said, according to CNN.
Trump has reacted in the past to Fox coverage with tweets and comments.
The president's tweet prompted a strong response from some critics, including former Democratic Rep. Gabrielle Giffords of Arizona.
"Mr. President, every day we are having a gun debate because every day 90 people in our country die from gun violence. Many of them are kids," Giffords tweeted.
Giffords survived a 2011 shooting and is now a leading advocate for curbing gun violence. She established the Americans for Responsible Solutions non-profit, an anti-gun violence advocacy group.
During the 2016 election campaign, Trump received support from the National Rifle Association and other pro-gun lobby groups. They hoped he would increase the number of Second Amendment advocates on the Supreme Court, The Hill reported.
In other tweets June 4, Trump criticized London Mayor Sadiq Khan, alleging that he had told people not to be alarmed.
Khan described the attack as a "deliberate and cowardly attack on innocent Londoners," the BBC reported.
Trump went on to argue that the London attack showed the need for the implementation of his travel ban, tweeting, "We must stop being politically correct and get down to the business of security for our people. If we don't get smart it will only get worse," according to Salon.