Volunteers clean a CVS pharmacy Tuesday, April 28, 2015, in Baltimore, in the aftermath of rioting following Monday's funeral for Freddie Gray, who died in police custody. Hundreds of volunteers are cleaning up the wreckage left by rioters in the neighborhood where Freddie Gray was arrested.

Image Credit: AP Photo/Matt Rourke

BALTIMORE - National Guardsmen took up positions across the city and hundreds of volunteers swept broken glass and other debris from the streets Tuesday, the morning after riots erupted following the funeral of a black man who died in police custody.

The streets were largely calm in the morning and into the afternoon, but authorities remained on edge against the possibility of another outbreak of looting, vandalism and arson.

The city was under a 10 p.m.-to-5 a.m. curfew, all public schools were closed, and the Baltimore Orioles cancelled their Tuesday night game at Camden Yards. National Guardsmen in helmets with face shields surrounded City Hall, standing behind bicycle-rack barriers.

"We're not going to have another repeat of what happened last night," Maryland Gov. Larry Hogan vowed after a visit to a West Baltimore neighbourhood where cars were burned and windows smashed. "We're going to make sure we get Baltimore back on track."

Hogan said there are "a couple of thousand" National Guardsmen and police officers in Baltimore, with more on the way.

The rioting was the worst such violence in the U.S. since the turbulent protests that broke out over the death of Michael Brown, the unarmed black 18-year-old who was shot by a white police officer in Ferguson, Missouri, last summer.

This is also the first time the National Guard has been called out to quell unrest in Baltimore since 1968, when some of the same neighbourhoods burned for days after the assassination of the Rev. Martin Luther King Jr.

At the White House, President Barack Obama called the deaths of several black men around the country at the hands of police "a slow rolling crisis." But he added that there was "no excuse" for the violence in Baltimore, and said the rioters should be treated as criminals.

"They aren't protesting. They aren't making a statement. They're stealing," Obama said.

As firefighters doused smouldering fires, political leaders and residents called the violence a tragedy for the city and lamented the damage done by the rioters to their own neighbourhoods.

The uprising started in West Baltimore on Monday afternoon, hours after the funeral for 25-year-old Freddie Gray, whose death has become the latest flashpoint in the national debate over the police use of deadly force against black men. By midnight, the rioting had spread to East Baltimore and neighbourhoods close to downtown and near the baseball stadium.

Rioters set police cars and buildings on fire, looted a mall and liquor stores and hurled rocks, bottles and cinderblocks at police in riot gear. Police responded occasionally with pepper spray or cleared the streets by moving in tight formation, shoulder to shoulder.

At least 20 officers were hurt, one person was critically injured in a fire, more than 200 adults and 34 juveniles were arrested, and nearly 150 cars were burned, police said.

"They just outnumbered us and outflanked us," Baltimore Police Commissioner Anthony Batts said. "We needed to have more resources out there."

The governor had no immediate estimate of the damage.

"I understand anger, but what we're seeing isn't anger," Baltimore Mayor Stephanie Rawlings-Blake lamented. "It's disruption of a community. The same community they say they care about, they're destroying. You can't have it both ways."

On Tuesday morning, hundreds of volunteers helped shopkeepers clean up as helmeted officers blocked a stretch of North Avenue in the neighbourhood where Gray was arrested. Hardware stores donated trash bags and brooms.

With schools closed, Blanca Tapahuasco brought her three sons, ages 2 to 8, from another part of the city to help sweep the brick-and-pavement courtyard outside a looted CVS pharmacy.

"We're helping the neighbourhood build back up," she said. "This is an encouragement to them to know the rest of the city is not just looking on and wondering what to do."

CVS store manager Haywood McMorris said the destruction didn't make sense: "We work here, man. This is where we stand, and this is where people actually make a living."

The violence set off soul-searching among community leaders and others, with some suggesting the uprising was about more than race or the police department — it was about high unemployment, high crime, poor housing, broken-down schools, and lack of opportunity in Baltimore's inner-city neighbourhoods.

The city of 622,000 is 63 per cent black. The mayor, state's attorney, police chief and City Council president are black, as is 48 per cent of the police force.

"You look around and see unemployment. Filling out job applications and being turned down because of where you live and your demographic. It's so much bigger than the police department," said Robert Stokes, 36, holding a broom and a dustpan on a corner where some of the looting and vandalism took place.

He added: "This place is a powder keg waiting to explode."

The Rev. Jesse Jackson visited the burned-out CVS and similarly said the violence, while inexcusable, reflected the alienation of unemployed people in neighbourhoods full of empty homes and vacant lots.

He urged Obama to set up a committee from the departments of Housing, Health, Labor and Education to create a jobs program to revive the neighbourhood and turn it into an example for the rest of the country.

In the aftermath of the riots, state and local authorities found themselves responding to questions about whether their initial response had been adequate.

Rawlings-Blake waited hours to ask the governor to declare a state of emergency, and the governor hinted she should have come to him earlier.

"We were trying to get in touch with the mayor for quite some time," Hogan said Monday evening. "She finally made that call, and we immediately took action."

Asked if the mayor should have called for help sooner, however, Hogan replied that he didn't want to question what Baltimore officials were doing: "They're all under tremendous stress. We're all on one team."

Rawlings-Blake said officials initially thought they had gotten the unrest under control.

Maryland National Guard spokesman Lt. Charles Kohler said that about 2,000 members would be deployed through the day and that the force could build to 5,000.

Also, State Police said they were putting out a call for up to 500 additional law enforcement officers from Maryland and as many as 5,000 from around the mid-Atlantic region.

With the city bracing for more trouble, several area colleges closed early Tuesday including Loyola University Maryland, Johns Hopkins University and Towson University.

Gray was arrested April 12 after running away at the sight of police, authorities said. He was held down, handcuffed and loaded into a police van. Leg cuffs were put on him when he became irate inside. He died of a spinal cord injury a week later.

Authorities said they are still investigating how and when he suffered the injury — during the arrest or while he was in the van, where authorities say he was riding without being belted in, a violation of department policy. Six officers have been suspended with pay while the investigation continues.

While they are angry about what happened to Gray, his family said riots are not the answer.

"I think the violence is wrong," Gray's twin sister, Fredericka Gray, said late Monday. "I don't like it at all."

In 1968, when Baltimore and many other U.S. cities erupted in flames over the assassination of King, the state of Maryland called up 6,000 Guardsmen to restore order in the city, and 2,000 active-duty federal troops were sent in, too. At least six people died in the chaos, and some neighbourhoods still bear the scars.

News from © The Associated Press, 2015