Boston Mayor Marty Walsh, Police Commissioner William Gross and Suffolk County District Attorney Rachael Rollins drew sharp distinctions Monday between the tenor and intent of peaceful afternoon protests Sunday and acts of violence and property damage that night.

The comments came the day after thousands took to the streets of Boston protesting racism and police brutality. The last peaceful protest began in Nubian Square as the sun set and ended at the State House. As the calm crowd began to disperse, orderly demonstration morphed into a disturbance that yielded 53 arrests, plus one summons, and 18 civilians and 9 officers transported to hospitals.

Walsh called the nightime unrest an “attack,” on the city. “We can’t allow violence to take away our focus,” he said.

“I’m certainly going to do everything I can to keep our city safe. But also, I’m not going to let that distract us from what George Floyd’s memory means. What Ahmaud Arbery’s memory means. What Breonna Taylor’s memory means. What Tamir Rice’s memory means. Trayvon Martin’s memory means,” Walsh said, invoking the names of slain African Americans whose deaths became viral hashtags over the last decade.

Rollins, who pledged to prosecute the arrested suspects, said she’s exhausted from seeing police killings play out repeatedly.

“This burning rage that you are seeing when you turn your TV on, or you hear in my voice is real,” she said, pointing to footage of black people killed in police-involved shootings.

“We should be proud that we have a commissioner in Boston who uses his voice to say this is unacceptable,” Rollins said, referring to Gross. “But I want to remind you, the commissioner is management and the commissioner is not the rank-and-file police officers that go out every single day and interact with our overwhelmingly poor black and brown communities and people are fed up and exhausted.”

Gross referred emphatically to George Floyd’s killing in Minneapolis last week as a “murder” and said “voices have to be heard, and black lives do matter.”

“Those voices speaking out against murderous acts that were committed in Minneapolis have be heard and move us along to where we can better serve the community together,” he said. “Police and community, community policing.”

Later, Gov. Charlie Baker also commented on the demonstrations calling George Floyd’s death a murder at the hands of the police.

“To the criminals and cowards who tarnished that night’s peaceful protest, I expect your day in court will come soon,” said Baker. “The people of Massachusetts cannot let these individuals succeed in their goal to sow chaos into the fabric of what is an important effort and movement.”

Gross announced Sunday’s arrests and noted that almost half of those arrested do not live in Boston.

Walsh acknowledged the health risks associated with protesting during a pandemic but indicated support for allowing more peaceful protests to occur, saying he believes in free speech and people’s right to protest.

Near Downtown crossing, business owners and workers began assessing damages.

Jessica Knez, co-owner of All Too Human boutique, estimated a multi-thousand-dollar loss to her inventory.

“It’s upsetting to be one of the many stores affected by last night’s violence,” she said. “I think a lot of people went to be around 9 or 10 seeing the end of the peaceful protest and didn’t quite realize that it turned violent.”

Knez noted her estimate does not include damage to store glass and fixtures.

Ed Rizzo of Abacus Glass and Mirror was called to replace glass at several buildings on School Street Downtown. He said was disheartened to see small businesses, already struggling from the coronavirus shutdowns, further damaged.

“It's a disgrace, to be honest,” he said in an interview with WGBH News. “People that have been out of work for two months, scraping to get by, and then they go in, people go in and take more money from them.