suggested Thursday that drugs were in part to blame for protests that turned violent following the fatal shooting of a black man by police in Charlotte, N.C., this week.

"If you're not aware, drugs are a very, very big factor in what you're watching on television at night," the Republican presidential nominee said during his energy speech in Pittsburgh.

ADVERTISEMENT He offered the remark, which was not in the prepared text of his speech provided by his campaign, while calling for a national anti-crime agenda. The Trump campaign later said the candidate was merely referring to reports of increases in the number of drug-related deaths. Trump kicked off his speech by commenting on the "turmoil" in the country, saying "it seems to be a never-ending problem." "Many Americans are watching the unrest in Charlotte unfolding right before their eyes on their TV screens. Others are witnessing the chaos and the violence firsthand," he said. "Many Americans are watching the unrest in Charlotte unfolding right before their eyes on their TV screens. Others are witnessing the chaos and the violence firsthand," he said.

Trump said the U.S. looks "bad" on the global stage when such incidents spring up. "How can we lead if we can't even control our own cities?" he said, calling for more law enforcement in Charlotte and elsewhere to crack down on violence. "How can we lead if we can't even control our own cities?" he said, calling for more law enforcement in Charlotte and elsewhere to crack down on violence.

Reports of overturned trash cans with their contents on fire, smashed car windows and looting followed a second night of violence in Charlotte late Wednesday.

Trump said that while citizens have a right to "peacefully assemble, protest and demonstrate ... there is no right to engage in violent disruption, or to threaten the public safety and peace of others."

“There is no compassion in tolerating lawless conduct. Crime and violence is an attack on the poor and will never be accepted in a Trump administration. Never, ever,” Trump said.

Charlotte's police chief said Thursday that the department would not release to the public video showing the shooting of Keith Lamont Scott.

- This story was updated at 4:41 p.m.