Four people were arrested Saturday night after clashes between protesters and police in the Chinatown area of downtown Washington, authorities said.

The arrests came after a skirmish as a group of about 100 marchers were wrapping up after a night of demonstration. The group was protesting police violence against people of color, but it was unclear what started the clash.

Police on Sunday said Steve Chang, 28, of no fixed address; Michael Klaus, 51, of Alexandria; and Adam Cunningham, 25, of Capitol Heights were arrested and accused of assault on a police officer and possession of a destructive device. Police said the devices included Roman candles, bottle rockets and other fireworks.

A male 15-year-old from Alexandria also was arrested and accused of assault on a police officer, possession of a destructive device and possession of a prohibited weapon, which authorities said was an ax.

Police said the four were in custody Sunday, with court appearances set for Monday.

According to a police report, officers saw the teen throw an ignited firework toward several officers. During a search, police found that he had additional fireworks and an ax, the report said. Officers detained and arrested the three men as they were arresting the teen, according to the report.

Bicycle officers swarmed and pushed back the crowd on Saturday as they tried to apprehend several demonstrators dressed in black, as other protesters tried to pull them free. Demonstrators lobbed a large firework that exploded amid the police line at Seventh and H streets. Others tossed water and water bottles, and some threw themselves at the police line while trying to free the arrestees.

D.C. police marched the dwindling crowd of about 45 people west along H Street until the crowd thinned.

The protest started at about 8:30 p.m. with a rally at Cobb Park at Second and H streets. The protesters made speeches and chanted the names of people of color who were killed in police-involved incidents, including George Floyd, Adam Toledo, Daunte Wright and Karon Hylton, who collided with a van while fleeing D.C. police on a Revel electric scooter.

Protesters then marched to Union Station, where police moved in after people spray-painted graffiti on a Christopher Columbus statue and a flare they threw caught fire at the base of the structure. Protesters headed toward the Chinatown Arch and were beginning to disperse about 10:45 p.m. when police made the arrests.

On Friday night, about 200 protesters clashed with police along the 14th Street corridor.