Briscoe Cain, a member of the Texas House of Representatives, had posted a Twitter message during Thursday’s Democratic debate in Houston, after O’Rourke said he planned to take away high-powered weapons from civilians if elected president.
“Hell yes, we’re gonna take your AR-15,” O’Rourke, a former congressman from El Paso, Texas, tweeted during the debate.
“My AR is ready for you Robert Francis,” Cain responded, using O’Rourke’s birth name.
At that point, O’Rourke made it clear he didn’t interpret Cain’s tweet to be a joke.
“This is a death threat, Representative,” O’Rourke wrote. “Clearly, you shouldn’t own an AR-15—and neither should anyone else.”
Cain replied: “You’re a child Robert Francis.”
Such weapons have become a topic of debate nationally after recent mass shootings – but particularly in Texas, where 22 people were fatally shot at a Walmart store in O’Rourke’s home city of El Paso on Aug. 3 and eight people were fatally shot in a suspect’s shooting spree in the Midland-Odessa area on Aug. 31.
O’Rourke, 46, served in Congress from January 2013 until earlier this year. He launched his 2020 presidential bid after generating national name recognition during a high-profile but failed U.S. Senate run against incumbent Ted Cruz, a Republican.
O’Rourke has argued for a mandatory buyback of assault weapons, among other gun control measures.
Cain, 34, is a Republican from Baytown who represents Texas’ 128th District, covering part of Harris County.
The website VoteSmart.org shows that Cain’s pro-Second Amendment votes this year have included support for allowing handguns at places of worship; allowing the storage and transportation of firearms in school parking areas; and authorizing law enforcement officers to carry weapons on school property.
In March, Cain drew attention to a class assignment at a Texas school that he argued was trying to promote a teacher’s anti-Trump agenda.
In February, Cain was among a group of state lawmakers who proposed using state money to help build a U.S.-Mexico border wall amid stalled federal efforts.
Fox News’ Paul Steinhauser contributed to this story.