Maryland Gov. Larry Hogan declared a state of emergency and activated the National Guard late Monday "to address the growing violence and unrest in Baltimore City" that resulted in fires, looting, injured police officers and more than two dozen arrests.
"All state agencies are actively engaged in this situation," the governor said at a press conference. And Maryland State Police Col. William Pallozzi said authorities were requesting up to 5,000 additional law enforcement officers from the regional area.
Fifteen officers were reportedly injured when protests turned violent in Baltimore Monday afternoon after a "group of juveniles" faced off with police near Mondawmin Mall. Police used tear gas and pepper spray to control the crowds, MSNBC's Chris Hayes reported.
"This is not protesting. This is not your First Amendment rights. This is just criminal acts," Baltimore Police Chief Anthony Batts told reporters late Monday, adding that all the injured officers were expected to recover.
Tensions have run high in the city since Freddie Gray, a 25-year-old black man, died on April 19 of what his family’s attorney said was a severed spine that allegedly occurred after Gray was arrested on a weapons charge on April 12.
About 10 Maryland National Guard trucks arrived in Baltimore late Monday, according to NBC News' Stacy Klein, carrying approximately 100 soldiers. As of approximately 8 p.m. ET Monday, two officers remained hospitalized and at least 27 people were arrested. A CVS drugstore was looted and set on fire. Multiple cars, including police vehicles, were seen in flames and burned out. And a senior center under construction in Baltimore was seen engulfed in flames, but it was not immediately clear if the roaring blaze was connected to the unrest in the city.
For their part, Gray's family condemned the violence via a Facebook post from their attorneys: "Freddie Gray's family is watching the looting and rioting and is upset, sad, angry. They are begging people to stop this. #FreddieGray #BaltimoreRiots." "I don’t agree with the violence … I think the violence is wrong," said Fredricka Gray, Freddie Gray's sister.
"This is lawless gangs of thugs roaming the streets causing damage to property and injuring innocent people," Gov. Hogan said, "and we’re not gonna tolerate that." Late Monday, the Baltimore Police Department tweeted that "groups of violent criminals are continuing to throw rocks, bricks and other items at police officers."
In a press conference late Monday, Baltimore Mayor Stephanie Rawlings-Blake distinguished between the weekend's peaceful protesters and those who resorted to violence on Monday, calling the perpetrator's of Monday's looting "thugs." Rawlings-Blake also announced a city-wide curfew, beginning Tuesday, from 10 p.m. until 5 a.m. The curfew will be in effect for a week, and extended as necessary. A juvenile curfew is already in place, she said -- 9 p.m. for those under 14, and 10 p.m. for juveniles over 14. Baltimore public schools will be closed Tuesday.
"This is one of our darkest days as a city," Rawlings-Blake said in a later statement to reporters. "We know that the world is watching, and we cannot allow our city to devolve into chaos because of a a small group of criminals that are moving throughout our city."
In stark contrast to the violent unrest, a group of protesters, led by Rep. Elijah Cummings -- the U.S. representative for Maryland's 7th Congressional District, which covers parts of Baltimore -- linked arms and marched on the sidewalks Monday evening, singing, "This Little Light of Mine."
Loretta Lynch -- on her first official day as U.S. attorney general -- issued a statement denouncing "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." Lynch noted that the DOJ "stands ready to provide any assistance that might be helpful" and reiterated that "The Civil Rights Division and the FBI have an ongoing, independent criminal civil rights investigation into the tragic death of Mr. Gray," adding that "The department's Office of Community Oriented Policing Services has also been fully engaged in a collaborative review of the Baltimore City Police Department." Lynch promised that Justice Department officials would soon travel to Baltimore to "meet with faith and community leaders, as well as city officials."
"We will find the people responsible and we will put them in jail," Capt. Eric Kowalczyk, a Baltimore PD spokesman, said.
The Baltimore Police Department said in a press release Monday that it "received credible information that members of various gangs including the Black Guerilla Family, Bloods, and Crips have entered into a partnership to 'take-out' law enforcement officers."
Late Monday, the Baltimore Orioles announced that they would postpone their Monday night baseball game against the Chicago White Sox "[a]fter consultation with Baltimore City Police."
The White House and Gov. Hogan were monitoring the situation. "Today's looting and acts of violence in Baltimore will not be tolerated," Hogan said in a statement. "In response, I have put the Maryland National Guard on alert so they can be in position to deploy rapidly as needed."
President Obama spoke to Mayor Rawlings-Blake Monday, according to a press release from the White House. "The President highlighted the Administration's commitment to provide assistance as needed and will continue to receive updates on the situation from Attorney General Lynch and White House Senior Advisor Valerie Jarrett," the statement said. Gov. Hogan said he also spoke to the president Monday evening.
David Simon, creator of the legendary Baltimore crime drama "The Wire" and a former reporter for The Baltimore Sun, called for an end to the violent protests. "There was real power and potential in the peaceful protests that spoke in Mr. Gray’s name initially, and there was real unity at his homegoing today," Simon said on his website. "But this, now, in the streets, is an affront to that man’s memory and a dimunition of the absolute moral lesson that underlies his unnecessary death."
Former Maryland governor and likely 2016 presidential hopeful Martin O'Malley -- who served as Baltimore's mayor from 1999 to 2007 -- issued a statement late Monday expressing grief over the situation. "I'm saddened that the City I love is in such pain this night," O'Malley said. "All of us share a profound feeling of grief for Freddie Gray and his family. We must come together as one City to transform this moment of loss and pain into a safer and more just future for all of Baltimore's people."
Earlier Monday, thousands of mourners descended on New Shiloh Baptist Church to attend Gray's funeral. Meanwhile, Baltimore police said extra officers were patrolling the streets after “a small contingent” of the at least 1,000 people who demonstrated Saturday became violent. Those protesters were “mostly peaceful,” police said in a statement, but some vandalized stores and police vehicles, leading to 34 arrests.
Authorities have not disclosed what caused Gray’s injuries. A cell phone camera captured him being pinned to the ground and then loaded into a police van. Police Commissioner Anthony Batts said Friday that Gray wasn’t seat-belted while he was being transported in the van and that officers should have gotten him medical care immediately following his detainment.
Since Gray's death, residents have taken to the streets daily to demand answers.
Additional reporting by NBC News' Elisha Fieldstadt and msnbc's David Taintor.