Police said they've arrested a man they said was one of the shooters on Saturday in Columbia Heights.
Four people were shot, including innocent bystanders, and one person died when two men exchanged bullets along the parade route of the Caribbean Festival. Authorities said the incident was part of an inter-gang dispute.
Chief Cathy Lanier said MPD arrested Terry Jiminez, age 19, of Buffalo, N.Y., in the incident. She said Jiminez, who is known to frequent the 11th Street area of D.C., was the aggressor in the shooting, though he claimed to have fired in self-defense, according to court documents.
The shooting stemmed from a standoff between two groups of people, NBC Washington's Derrick Ward reported. The groups exchanged gestures as the standoff heated up and then exchanged gunfire. Jiminez was among the four people shot.
"This is why we go so aggressively after gangs, because they are ruthless with their violence," Lanier said, later adding, "They don't care that a parade is going on."
Jiminez was charged with murder two while armed and other charges. He was ordered held without bond until his next court appearance on July 19.
Leaders of Peaceoholics, a non-profit group that works to end inner-city violence in D.C., claim that Saturday's deadly shooting following the Caribbean Day Parade was the result of two rival crews.
They said they brokered peace between the leaders of the two crews years ago, and the gun violence in Columbia Heights ceased for a while.
The group alleges in its press release that a lack of city funding and support caused their efforts to fall apart. Today, they are calling for an investigation into how the city funds groups like the Peaceoholics.
The annual Caribbean Day Parade on Georgia Avenue in Northwest attracts hundreds of spectators. Many had left before the shooting began. Police said 43-year-old Robert Foster Jr., an innocent bystander, was shot and killed during the shooting.
Ward 1 Council member Jim Graham told NBC Washington that one of the people injured was the intended target of another shooting that took the life of another innocent bystander -- 17-year-old Lucky Pannell, who was shot and killed while sitting on her front porch last February.
Cell phone video of two of the shooting victims, including one woman, went viral on YouTube but have since been marked as private.
Lanier said about the festival itself, "It's been a peaceful event for many years."
Check back with NBC Washington for more updates as the story develops today.