Former Rep. Gabby Giffords, D-Ariz., urged lawmakers to “find the courage” to pass gun control legislation following a deadly high school shooting in Florida on Wednesday

“Even in our grief, we must summon the courage to fight against this fear,” she said on Twitter Wednesday. “We must find the courage to imagine a country where these massacres do not occur. Our leaders must find the courage to escape the confines of their politics & pursue the moral necessity of peace & safety.”

“Every day we fail to take action, we chose this fate,” she said in a separate tweet. “We tolerate politicians who fail to acknowledge the crisis and vote against our safety. We let our gun violence epidemic continue day after deadly day.”

Giffords concluded by urging Congress to enact legislation that would “protect our children” and prevent harmful individuals from accessing guns.

“And if Congress won’t act, American voters must,” she said.

Giffords has become a leading advocate for anti-gun violence causes, after she was shot in the head in 2011 during a “meet and greet” for her at a parking lot. Six people were killed in the attack.

She has co-founded Americans for Responsible Solutions, a nonprofit organization that supports gun control, with her husband, retired astronaut Mark Kelly.

Giffords’ comments were made in response to a shooting at a Florida high school that took the lives of at least 17 people, according to law enforcement officials.

Police identified the shooting suspect as Nikolas Cruz, 19, who had been previously expelled from Marjory Stoneman Douglas High School, where the shooting took place.