(CNN) —  

The field of announced and likely potential presidential contenders used Twitter and the airwaves to respond to the killing of an unarmed black man at the hands of a white police officer, which was caught on video.

Here’s what they had to say:

Hillary Clinton

The former secretary of state said on Twitter that she was “praying” for the family of the victim, Walter Scott, and called the shooting “heartbreaking and too familiar.”

“Praying for #WalterScott’s family. Heartbreaking & too familiar. We can do better - rebuild trust, reform justice system, respect all lives.”

Ben Carson

The neurosurgeon said Thursday on CNN he was “aghast” when he watched the video of the South Carolina incident, but said race was “totally irrelevant” in the shooting.

“I mean a police officer you know shooting down a citizen of the United States – really doesn’t matter what the color of them is” Carson said Thursday on “New Day.” “It wasn’t about race. It was about you know the abuse of power and position.”

Carson had also called the shooting “an execution” in an interview Wednesday with Buzzfeed News.

Carson on Thursday called the shooting an opportunity for law enforcement to come out and condemn the actions of Scott’s killer, North Charleston officer Michael Slager, who is now facing a murder charge.

Rand Paul

The Kentucky senator who launched his presidential campaign this week, called the shooting a “terrible tragedy.”

“I hope justice does occur,” Paul said Wednesday on CNN.

But Paul also cautioned against taking the situation and making it “representative of the whole.”

“I think when you look at police across our country, 98, 99% of them are doing their job on a day-to-day basis and aren’t doing things like this,” Paul said.

Martin O’Malley

Former Maryland Gov. Martin O’Malley, who could challenge Clinton for the Democratic nomination, pointed to the concern of many who said the police officer would have likely evaded justice had there been no video.

“It shouldn’t take a video to ensure justice,” O’Malley tweeted Wednesday.

“My thoughts & prayers are w/Walter Scott’s family. Far too many families across the nation have endured tragic losses like this one,” he tweeted. “This video is appalling but it shows why accountability & transparency are so important.

Scott Walker

Wisconsin Gov. Scott Walker called the incident “just horrific.”

“That video just shook my very human being to think that someone would do that,” Walker said Wednesday on Fox News. “And I think anyone in law enforcement knows that that’s not the way people are trained to act and I send out my sympathy to the family involved there.”

Lindsey Graham

Lindsey Graham, South Carolina’s senior senator, called the video of the shooting “horrific” and said it was “very difficult to watch and deeply troubling on many fronts.”

“I have full confidence this incident will continue to be investigated by the relevant authorities, the legal process will proceed, and ultimately, justice will be done,” Graham said Wednesday in a statement. “I also know the actions of the officer in this situation do not accurately reflect on the many valuable contributions made by thousands of law enforcement officers in South Carolina and across our nation.”