Democratic presidential candidate Beto O’Rourke has reported a Texas lawmaker to the FBI after he tweeted that his assault rifle “is ready for you”.
Republican legislator Briscoe Cain’s tweet was deleted by Twitter after the Democrat called it a “death threat”.
Mr Cain tweeted after Mr O’Rourke called during a live TV debate on Thursday night for a ban on semi-automatic rifles.
He stated his plan to confiscate some types of guns.
“Hell, yes, we’re going to take your AR-15,” Mr O’Rourke, a former Democratic Texas congressman, said on the debate stage in Houston.
“My AR is ready for you Robert Francis,” tweeted the 34-year-old Republican, using Mr O’Rourke’s legal first name. AR stands for Armalite rifle.
Mr O’Rourke responded: “Clearly, you shouldn’t own an AR-15 – and neither should anyone else.”
Some Texas lawmakers criticised the tweet, which Twitter took down, saying “it violates our rules for threats of violence”.
Mr Cain later hit back on Twitter, calling Mr O’Rourke “a child”.
A spokesman for Mr O’Rourke said the Texas state legislator had been reported to the FBI.
In 2018, police were called to remove Mr Cain from the state Democratic convention after he showed up with a pistol and pro-gun pamphlets, the Fort Worth Star-Telegram reported.
Mr O’Rourke has made gun control a key plank of his White House campaign since 22 people were killed in a rampage at a Walmart in his hometown of El Paso, Texas, last month.