BALTIMORE - Authorities ordered thousands of police and National Guard troopers to back up beleaguered officers in the US city of Baltimore on Monday after riots triggered by anger over alleged police brutality.
Stone-throwing mobs clashed with police and attacked local businesses after the funeral of a black man who died of spinal injuries apparently suffered during his arrest earlier this month.
Despite appeals for calm from 25-year-old Freddie Gray's family, gangs of mainly African American youths fought street battles with police that left 15 officers hurt. Twenty-seven people were arrested, police said.
Several local businesses were looted and police vehicles burnt out as disturbances spread through the port city, causing Maryland to declare a state of emergency.
While most of the violence was in the west of the city, as night fell, a large building was also ablaze on Baltimore's east side.
Mayor Stephanie Rawlings-Blake appealed for calm and imposed a nighttime curfew in the city of 620,000 from 10:00 pm Tuesday (0200 GMT Wednesday).
Maryland police superintendent Colonel William Pallozzi said he had ordered 500 police to the city and requested 5,000 more from the broader Mid-Atlantic region.
And National Guard commander Adjutant General Linda Singh said she had 5,000 troopers ready and would deploy them in "massive force" to protect people and property.
"Too many people have spent generations building up this city for it to be destroyed by thugs," Rawlings-Blake said, herself facing criticism that the city had been slow to act.
Rioters prowled the city in small roving gangs, ransacking shops. Looters queued outside a shopping mall, stealing armloads of merchandise, and then drove away.
Funeral, then violence
Rioting erupted soon after Gray was buried - possibly spurred by a cryptic social media message declaring an after-school "purge," street slang for random acts of lawlessness.
The University of Maryland's downtown campus, corporate offices and the city's famous Lexington Market shut down early.
And the Baltimore Orioles baseball team cancelled its evening game against the visiting Boston Red Sox as a precaution.
City schools were to be closed on Tuesday.
President Barack Obama was briefed on the rapidly evolving situation by Rawlings-Blake and his newly sworn in Attorney General Loretta Lynch, the White House said.
Thousands had converged on New Shiloh Baptist church in Baltimore's poverty-ridden Sandtown neighborhood earlier to pay respects to Gray.
His death was the latest in a string of high-profile confrontations between African Americans and police.
Last year's fatal shooting of unarmed teenager Michael Brown by a white police officer in Ferguson, Missouri triggered coast-to-coast protests.
Gray's grieving family had explicitly asked for no protests.
"Today of all days, the family was clear this was a day of sacred closure," said pastor Jamal Bryant of the city's Empowerment Temple church, who delivered the eulogy.
"So for us to come out of the burial and walk into this is absolutely inexcusable. I'm asking every young person to go back home." Violence had also erupted on Saturday when 34 people were arrested, and six police officers injured, after an orderly rally for Gray outside Baltimore city hall.
In the hours before Monday's riots, police announced they had received a "credible threat" that criminal gangs in Baltimore had "entered into a partnership to 'take out' law enforcement officers." At the funeral, Gray's body was in a white casket next to a Los Angeles Dodgers baseball cap and a sign reading "Peace y'all." Crowds swayed to hymns, chanting, "Justice shall prevail, peace will prevail" in the church, where a photo of Gray was displayed among floral wreaths.
Supporters, many dressed in white, filled the building's 2,200 seats and hundreds of others stood, with the words "Black lives matter and all lives matter" projected on the wall.
'Epidemic of murders'
Civil rights activist Jesse Jackson denounced the "epidemic of murders in the country." "We have become too violent, too full of hate," Jackson told reporters before the service.
"We need training, employment, housing, access to health, a reconstruction project. Poverty is a weapon of mass destruction." Tensions have been on the rise in Baltimore since Gray's death, which his family's lawyers say was caused when his spine was mostly severed following his arrest.
Six officers have been suspended with pay pending the outcome of a police investigation that is to be submitted to state prosecutors by Friday.
The US Justice Department, which was already looking into Baltimore's use of force, has also opened a federal civil rights probe.
Police confirmed Gray had requested medical help and an inhaler after he was detained and have acknowledged that he should have received medical attention sooner.
Gray's arrest was caught on video by bystanders, and he can be heard howling in apparent pain as his limp body is dragged into the van.