After a gunman opened fire at a Florida high school, killing 17 people, US Representative Seth Moulton tweeted that President Trump should “get off his ass” when it comes to gun control.

After the harrowing incident, Trump tweeted: “No child, teacher or anyone else should ever feel unsafe in an American school.”

Moulton, a Massachusetts Democrat, then quote-tweeted the president, saying he agreed with Trump’s sentiment, adding: “I invite him to get off his ass and join me in trying to do something about it.”

This isn’t the first time Moulton has been vocal on gun violence. After dozens of people died in a shooting in Las Vegas in October, Moulton tweeted to House Speaker Paul Ryan, “How many Americans have to die before you do your job?”