(CNN) —  

Republican presidential hopeful Ben Carson urged parents in Baltimore to “take control of your children” and keep them away from the city’s streets as violent protests unfold there.

Carson, the neurosurgeon who once worked at Baltimore’s Johns Hopkins Hospital, said in a Facebook post Tuesday morning that it is “very sad and unfortunate to see the destruction taking place by irresponsible individuals.”

He was the latest 2016 presidential candidate to weigh in on the violent protests and tensions between police and African-American residents in the city, which erupted a week after 25-year-old Freddie Gray died in police custody after being denied medical attention.

“It is vital to remember that the best way to create positive change is through peaceful conversation and policy ideas that display a commitment to resolution,” Carson said in his Facebook post. “My thoughts and prayers are extended to those who are experiencing fear and loss during this troubling time, including the families of Mr. Gray and first responders/officers.”

Carson added: “I urge parents, grandparents and guardians to please take control of your children and do not allow them to be exposed to the dangers of uncontrolled agitators on the streets.”

During a radio appearance Monday evening, New Jersey Gov. Chris Christie said it’s too early for “a post-mortem on this,” and that he’d leave it to law enforcement officials to handle the situation.

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But Christie said more police departments should look like the one in Camden, New Jersey, where he said police have better assimilated into the community they serve by ditching their squad cars and hitting the streets on foot.

Another Republican contender, Sen. Ted Cruz of Texas, said that “targeting law enforcement for violence is wrong, and it cannot be allowed to persist.”

“Our government must perform its central functions and purposes: to preserve the peace, protect the people, and serve justice,” Cruz said.

“The government exists to ensure our domestic security — whether it’s from a city riot, or the threat of a terrorist attack on our homeland. We have to restore that trust and prove to the people we can make America safe again,” he said.

Former Arkansas Gov. Mike Huckabee said he is praying for Gray’s family and for safety in Baltimore. “Freedom of speech is valuable to all Americans, but rioting and criminal activity is no way to exercise that right,” he said.

In the Democratic field of candidates, one dark horse contender — Martin O’Malley, the former Maryland governor and Baltimore mayor — canceled a series of paid speeches in Ireland to return to his home city Tuesday.

Democratic front-runner Hillary Clinton said on Twitter that she is praying for peace and safety in the city, and that Gray’s death is “a tragedy that demands answers.”

RELATED: White House faces new racial crisis in Baltimore

CNN’s Ashley Killough contributed to this report.