Violent protests have taken place in Baltimore following the funeral of a black man who died in police custody, forcing Maryland Governor Larry Hogan to call for a state of emergency and activate the National Guard to help the city police establish security.
A week long citywide curfew will be imposed in Baltimore from 10 PM to 5 AM, starting on Tuesday.
About 1500 National Guards will be deployed in the city and another 5000 law enforcement officers have been requested from neighboring states.
The clashes between protesters and the police started in the neighbourhood where the funeral for Freddie Gray took place, who died on April 19 one week after receiving injuries while being arrested by the police.
In a short time, violence spread to the other parts of the city as the angry crowd of young protesters clashed with police - throwing rocks and burning cars while ignoring calls to disperse.
Colonel Darryl DeSousa from Baltimore’s police department said 15 police officers were injured in the clashes and two officers are still in hospital.
At least 27 people were arrested but the number is likely to rise as the police investigate security footage from the area.
The crowd set a pharmacy on fire after looting it, and burned several police cars.
“Today's looting and acts of violence in Baltimore will not be tolerated," Gov. Hogan said.
Baltimore City Public Schools will be closed on Tuesday and Baltimore’s Orioles baseball team announced they cancelled a game on Monday over of security reasons after consulting with the police.
Baltimore is located around 60 kilometres away from Washington DC, the capital of the United States.
President Barack Obama spoke with the governor on the phone and new Attorney General Loretta Lynch released a statement concerning the situation.
“I condemn the senseless acts of violence by some individuals in Baltimore that have resulted in harm to law enforcement officers, destruction of property and a shattering of the peace in the city of Baltimore,” Lynch said regarding the events in the city.
Earlier in the day, Baltimore police reported receiving a "credible threat" that several gangs were planning to try to "take out" law enforcement officers.
The police department did not give any details on the source of the threat or its relation to Gray’s death, but urged officers to take necessary precautions to ensure their safety.
Today’s funeral was preceded by days of protests over Gray's death in the latest outcry over U.S. law enforcement's treatment of minorities.
Thousands of people, including many members of congress, attended the ceremony in New Shiloh Baptist Church for Freddie Gray, who died on April 19, one week after his spine was injured during a police arrest.
"At 25, he had to feel that the walls were closing in," said the Rev Jamal Bryant of Empowerment Temple AME Church, who delivered the eulogy. "He had to feel boxed in" by poverty and lack of opportunity, just like many other young black men.
"When that black boy got out of the casket, that black boy said, 'No justice!'" Bryant said.
The crowd roared in response, "No peace!"
"No justice, no peace" has been a rallying cry in the Baltimore protests against police brutality.
U.S. Representative Elijah Cummings of Baltimore, one of numerous politicians at the funeral, vowed to see justice be done.
"It is on our watch," Cummings said. "We will not fail you."
Also at the funeral were Mayor Stephanie Rawlings-Blake and civil rights leader the Rev Jesse Jackson Sr, Gray's five sisters and other family members, and clergy from across the predominantly black city of 620,000 people.
President Barack Obama sent Broderick Johnson, the head of his initiative for minority males, to attend the funeral.