UPDATED 01/10/11 11:09 a.m.

WASHINGTON (CBS) — U.S. Senate Majority Whip Dick Durbin (D-Ill.) is calling on lawmakers and the media to tone down violent political language, in the wake of the Arizona shooting spree that killed six people and critically wounded U.S. Rep. Gabrielle Giffords (D-Ariz.)

More than a dozen people were shot in the Saturday incident in Tucson, Ariz., during a “Congress on Your Corner” event in a grocery store parking lot.

Following the shooting, several were quick to point out Giffords was one of 17 Democratic lawmakers that Republican Sarah Palin highlighted during the health care reform debates. Her political action committee sent out election material featuring maps of the U.S. with crosshair targets over the states where those lawmakers served.

Sarah PAC Crosshairs Map

(Credit: SarahPAC.com)

During the healthcare debate, Palin also posted to followers of her Twitter page “Don’t Retreat, Reload.”

Speaking to CNN on Sunday, Durbin specifically mentioned Palin’s rhetoric in a call to tone down political hostility.

“The phrase, ‘Don’t retreat, reload;’ putting crosshairs on Congressional districts as targets – these sorts of things, I think, invite the kind of toxic rhetoric that can lead unstable people to believe that this is an acceptable response, Durbin said.

A Palin staffer is defending the former Alaska governor and vice presidential nominee, saying she had “nothing whatsoever to do with this.”

“We never ever, ever intended it to be gun sights,” Palin aide Rebecca Mansour said in an interview with radio host and Palin supporter Tammy Bruce. “It was simply cross-hairs like you’d see on maps.”

On Saturday, Palin herself said her prayers are with Giffords and the other shooting victims.

Giffords, 40, was shot in the head at point-blank range and critically wounded. Killed in the shooting were Arizona U.S. District Judge John Roll, 63; Christine Taylor Green, 9, the granddaughter of former Cubs general manager Dallas Green; Dorothy Morris, 76, Phyllis Schneck, 79. Dorwin Stoddard, 76, and Gabe Zimmerman, 30.

A law enforcement source told CBS News that a man apparently stood up in the crowd during the town hall meeting, shouted something and then opened fire. Someone – possibly police or security – then shot at the gunman.

The suspect, Jared Loughner, 22, is due in court later Monday. He is charged with one count of attempted assassination of a member of Congress, two counts of killing an employee of the federal government and two counts of attempting to kill a federal employee. More charges are expected.

Investigators carrying out a search warrant at his parents’ home in a middle-class neighborhood found an envelope in a safe with the words “I planned ahead,” “My assassination” and the name “Giffords” next to what appears to be his signature.

Giffords, 40, who just started her third term in Congress, was reelected in November after defeating Republican and Tea Party favorite Jesse Kelly by a margin 49 percent to 47 percent.

CBS News contributed to this report.