(CNN) - Rep. Michele Bachmann wasn't laughing Monday at Herman Cain's "joke" about building an electrified fence on the U.S.-Mexico border.
Speaking to the media in Phoenix, the Minnesota congresswoman gave a full-throated endorsement of a border fence, but said that joking about the matter detracted from the gravity of the issue.
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"This is no laughing matter, the border fence," Bachmann said. "We've seen jokes made by presidential candidates about the fence. It is not a joke. This is a real issue, and this is a serious issue."
On Sunday, former Godfather's Pizza executive Herman Cain said remarks he made about an electrified border fence between the United States and Mexico were a joke.
Cain made the original comments Saturday at a rally in Tennessee during a bus tour through the state.
"When I'm in charge of the fence, we going to have a fence. It's going to be 20 feet high. It's going to have barbed wire on the top. It's going to be electrocuted, electrified," Cain said. "And there's going to be a sign on the other side that says it will kill you."
On NBC's "Meet the Press" Sunday, Cain said he was joking.
"That's a joke," Cain said. "I've also said America needs to get a sense of humor. That was a joke, OK."
On Monday, Bachmann said determining how to build a border fence was of the utmost importance for American security.
"It is important that we actually do complete the fence in every portion," Bachmann said.
She continued, "We need to look at terrain of the fence, and make sure we have the most appropriate fence that there is, and the most appropriate human intelligence on the ground."