Rioters plunged part of Baltimore into chaos Monday, torching a pharmacy, setting police cars ablaze and throwing bricks at officers just hours after the funeral of 25-year-old Freddie Gray, a black man who died from a mysterious spinal injury sustained while in police custody earlier this month.
The governor of Maryland, Larry Hogan, declared a state of emergency and activated the National Guard to help with the violence and rioting. He signed the order late Monday at the request of the city.
At an evening news conference Baltimore Mayor Stephanie Rawlings-Blake said the city is imposing a curfew, saying "thugs" were trying to tear down the city and incite violence. The curfew is set for 10 p.m. until 5 a.m. (EDT) for one week starting on Tuesday.
At least 15 officers were hurt, and some two dozen people were arrested during clashes Monday with hundreds of youths who pelted the officers with rocks, bricks, glass bottles and other objects.
Two officers remained hospitalized, police said.
Television footage showed at least one police cruiser in flames and crowds of looters breaking into stores. A pharmacy was set on fire later in the day.
The clashes started near the Mondawmin Mall, just blocks from Gray's funeral, and spread out over a wide area as a line of police officers pushed them back.
At one point, a police car was surrounded and destroyed by people jumping on it. Police initially showed restraint on Monday, but then began arresting people and prepared to use teargas and pepper spray.
In the late afternoon schools, businesses and train stations began closing in the city of 662,000 people, 40 miles (64 km) from the nation's capital.
The Baltimore Orioles professional baseball game was cancelled, as were all school trips scheduled into the city this week.
Freddie Gray's funeral
The riot occurred just hours after the funeral for Gray, whose family along with pastors and city officials had pleaded for peaceful demonstrations after some arrests and injuries at protests over the weekend.
"It is disappointing just a few hours after putting Gray to rest," Reverend Jamal Bryant who spoke at the funeral told reporters. "This is not what the family asked for today of all days. This was a day of sacred closure."
Freddie Gray Laid to Rest
Thousands of mourners gathered at a church to pay their respects to Gray, whose death became the latest incident sparking questions and protests about interactions between minorities and police in the United States.
Among those attending the funeral were Reverend Jesse Jackson and Maryland Congressman Elijah Cummings, whose district includes Baltimore. White House officials said Cabinet Secretary Broderick Johnson, who heads an initiative on minority men, represented President Barack Obama's administration.
Gray family attorney, Bill Murphy Jr., called on the officers involved in the incident to come forward and tell their side of the story.
"It's a corrosion on justice," said Murphy in remarks at the funeral. "And we're calling for the police, the six of them that are at least being partially, if not totally, implicated to come forward and to tell it all just like you tell our citizens to do."
Gray suffered severe spinal cord injuries following his arrest on April 12. Officials said Gray was not restrained properly while being transported in a police van.
Protesters have been demanding justice in daily demonstrations that have been largely peaceful, but some incidents of vandalism and violence were reported in a march on Saturday.
Meanwhile, the Baltimore Police Department reported a "credible threat" that some violent street gangs were planning to target police officers. Police have not clarified whether the threat was connected to the ongoing demonstrations.
Speaking on CBS television Sunday, Congressman Cummings said the relationship between police and communities is the civil rights cause for this generation. He added that it is still not exactly clear why Gray was arrested and the entire situation is "very upsetting."
Baltimore Mayor Stephanie Rawlings-Blake said Friday she wants to know why police officers apparently did not follow the policy requiring that all prisoners wear seatbelts while being transported, and why they did not call for medical assistance after Gray asked for it.
The police commissioner said officers were slow to recognize that Gray, who apparently had asthma, needed medical attention.
More information on the case is expected May 1, according to the Baltimore Police Department.
The agency placed six officers who had contact with Gray on paid administrative leave. The U.S. Department of Justice is investigating whether civil rights violations occurred.
A string of deadly confrontations between mostly white police and black men, and the violence it has prompted, will be among the challenges facing U.S. Attorney General Loretta Lynch, who was sworn in on Monday.
Following her swearing in, Lynch signaled that improving relations between police and the communities they protect will be high on her agenda.
"We can restore trust and faith both in our laws and in those of us who enforce them," she said.
President Barack Obama pledged the federal government's help to respond to the Baltimore riots. Lynch met with the president in the Oval Office Monday evening as violent scenes of rioting played out on television.
Some material for this report from Associated Press and Reuters.