At a campaign rally in North Myrtle Beach, South Carolina, on Tuesday, Marco Rubio deflected a supporter’s suggestion to “waterboard Hillary” with a laugh. “The press is here,” he said, the AP reports, before smiling and adding, “I didn’t hear what they said. I know it wasn’t a bad word.”

Tensions between Rubio and Ted Cruz, on display at the most recent Republican debate, have only heightened as the next primary draws closer. “This has been a pattern now with Ted,” Rubio said at a lunch with reporters in Summerville. “He has spent the last two weeks literally just making stuff up.”

“I just think it’s very disturbing [that] you can just come and make things up about people and believe no one is going to call you out on it. And it’s now become a pattern, so we have to clarify that we can’t let that stand unchallenged.” From the Guardian:

Rubio added that Cruz had misrepresented his position on a host of issues, including immigration, funding for Planned Parenthood, and same-sex marriage. Cruz and his allies have launched a series of attacks against Rubio aimed at portraying him as insufficiently conservative – even though Rubio holds one of the most conservative records in the US Senate.

By Tuesday evening, Rubio’s campaign spokesman Alex Conant was blasting Cruz in a fundraising email with an aggressive subject line: “Ted Cruz is a liar.”

“First it was lying about Marco on fundamental issues like life and marriage; now Cruz and his supporters’ attempts to slander and distort Marco’s record have reached a new low,” Conant wrote.

One ad by a pro-Cruz Super Pac was pulled down on Monday after a legal review determined it to be misleading in its charge that Rubio supported so-called “sanctuary cities” while shepherding a comprehensive immigration reform bill in 2013. Cruz also asserted that his Senate colleague shied away from standing at the forefront of the fight to defund Planned Parenthood, even though Rubio has voted numerous times to strip the women’s health organization of its federal funding.

The waterboarding suggestion later in the day on Tuesday came after Rubio promised to keep the U.S. base at Guantanamo Bay open “forever.”

Photo via AP Images. Contact the author of this post: brendan.oconnor@gawker.com.