In the wake of the shooting of Rep. Gabrielle Giffords (D-AZ) and 18 others, the Texas-based parent company of a Tuscon-area talk radio station has removed a billboard referring to a popular conservative talk show host as a "straight shooter."

The black billboard with white typewriter font surrounded by bullet holes promoting Rush Limbaugh's radio program was okayed by the promotions department of NewsTalk 790 KNST, Clear Channel said in a statement to Talking Points Memo Thursday.

The media conglomerate explicitly noted that Limbaugh had not authorized the billboard, which displayed in Tucson for the last few weeks.

"This particular ad - which used the common expression 'straight shooter' to describe Mr. Limbaugh's candid and direct style - was designed and contracted for by the local station's promotion department - not by Mr. Limbaugh's program," the statement said.

Clear Channel continued, "In the wake of the tragedy, Clear Channel Outdoor management in Tucson quickly elected to take down this ad - believing that discussion of its interpretation would not contribute to the desire for healing in the Tucson community."

This admission is the latest in a week filled with criticism of the flamboyantly violent nature of conservative political rhetoric after a gunman opened fire at a supermarket where a political rally was happening.

Roger Ailes, chief of operations at the right-wing Fox News network, reportedly told his employees to tone down their rhetoric on-air.

"You don't have to do it with bombast," he explained in an recent interview.

In spite of the call for moderation, Ailes still defended Fox News employee Sarah Palin and her use of gun terminology in political discourse.

Prior to the 2010 midterms, a post on Sarah Palin's Facebook page placed crosshairs over Rep. Giffords' congressional district. Palin said supporters should "reload" and use their votes to "aim for" the Democrat's defeat.

Giffords was shot in the head by a gunman Saturday, and remains in critical condition.

Pima County Sheriff Clarence Dupnik singled out Limbaugh for the "irresponsible" rhetoric he uses on his radio show.

"The kind of rhetoric that flows from people like Rush Limbaugh, in my judgment he is irresponsible, uses partial information, sometimes wrong information," Dupnik told ABC News. "[Limbaugh] attacks people, angers them against government, angers them against elected officials and that kind of behavior in my opinion is not without consequences."

There is no indication that the man that allegedly shot killed six and wounded 14 others in Arizona Saturday, 22-year-old Jared Loughner, was a fan of Fox News' Glenn Beck.

However, an ">image published to Beck's website, of the conspiracy host holding a handgun and posing like a character in a television action-drama, was also recently pulled offline.

With reporting by David Edwards and Eric W. Dolan.