If race relations have deteriorated in the United States then Barack Obama is to blame, according to some of the Republican contenders to succeed him in the White House.

On Saturday Bobby Jindal, the Louisiana governor who has not yet declared his candidacy for the GOP nomination, accused the president of having a divisive tone on race. Jindal was responding to a question about recent riots in Baltimore which followed the death in police custody of Freddie Gray, a 25-year-old African American man.

“We’re not just talking about Baltimore or some of the incidents recently, but I’ve said I think for quite some time the president continues to divide us,” Jindal told reporters following a speech at the South Carolina Freedom Summit, a conservative gathering of grassroots activists.

“He tries to divide us by gender, by age, by geography, by race – and I think that’s wrong. Part of his job is to unite us and bring us together.”

Jindal then tied the issue to the concept of “hyphenated Americans”, a concept he has frequently criticized as he weighs a bid for the White House in 2016. The first Indian American to be elected governor in the US had raised his distaste for “hyphenating” groups of Americans – referring to the use of “African Americans,” “Indian Americans” or “Asian Americans” – during his speech.

Asked again, however, about the treatment of African Americans at the hands of police, Jindal said: “Obviously any time somebody’s treated differently because of the color of their skin, whether it’s done by government or in the private sector or individuals, that’s sinful, it’s wrong.”

Over the last year, police brutality has risen to the forefront of national debate. The fatal shooting of 18-year-old Michael Brown in Ferguson, Missouri, last August by a white police offer led to months-long protests, as did the death of Eric Garner, who died after he was placed in a chokehold by New York City police despite stating several times that he could not breathe.

Obama has repeatedly called for national soul-searching on the issue. He also launched a task force on police accountability and called for $263m in funding so that law enforcement agencies could purchase body cameras.

President Obama has consistently driven wedges between people … on race, ethnicity, sexual orientation Representative Steve King

In South Carolina on Saturday, Iowa representative Steve King, one of the most conservative Republicans in Congress, also pointed the finger at Obama for stoking racial tensions.

“President Obama has consistently driven wedges between people,” King told reporters after speaking at the event. “And he perceives a difference on race, ethnicity, sexual orientation – wedge after wedge after wedge.

“I didn’t really imagine they were going to drive a wedge between the law and law-breakers. It is instinctive on the part of the president. That’s a level that I have not seen before.”

Asked if he was specifically blaming Obama for the riots in Baltimore, King said: “Yes.”

He added: “The culture has created that because they drove that culture in Ferguson and it multiplied itself in Baltimore and across the country.”

Ted Cruz, the Texas senator who was the first Republican to declare himself a candidate for president last month, has also stated that Obama “inflamed” racial tensions and was vilifying the police.

The president “has made decisions that I think have inflamed racial tensions – that have divided us rather than bringing us together”, Cruz told CNN last month. “He has exacerbated racial misunderstandings, racial tensions, from back at the beer summit [a 2009 White House meeting between Harvard professor Henry Louis Gates Jr and a white police officer] to a series of efforts to pit Americans against each other.

“And part of the problem is the way he advocates for any given plan is to paint … is to build a straw man of the opposition and then vilify caricatures.”