This browser does not support the Video element.
A shooting in Washington D.C. on Sunday has left one person dead and several others injured, including one police officer.
A spokesperson for the Metropolitan Police Department told Fox News that four people were shot at a Moechella event, including one police officer, who did not return fire at the crowded area.
Metropolitan Police Department Chief Robert J. Contee III said later the victims included a 15-year-old, who was pronounced dead at the scene, two adults, and the officer.
The MPD officer was shot in a lower extremity and is expected to survive, the chief said. The adults were transported to a local hospital.
Chief Contee said the shooting took place at approximately 6 p.m. at an "unpermitted event" in connection with Moechella, which is described as an "Advocacy Festival Amplifying the Culture of Washington DC."
"We need to make sure individuals are held accountable for their actions," Contee said.
Video from the scene of the shooting shows officials helping multiple people lying on the street.
"When you have large gatherings in a dense area, it only takes one person with a firearm to make this a dangerous setting," the police chief added.
Contee also said several illegal firearms were recovered by police officers earlier in the night and at least one firearm had an extended magazine. The firearm that was used on the officer was not recovered, he said.
Washington, D.C. Mayor Muriel Bowser also spoke during the presser, calling for "accountability" for those responsible.
"We have a child that was killed at an event that didn’t have proper planning, with people with guns involved," Bowser said. "Even with police managing crowds on-site, someone used a gun and now a child is dead."
"We need some accountability here," she added.
The event's marketing had convinced the MDP that a heavy police response would be necessary and over 100 officers were sent to monitor it, Contee said.
Read more on FoxNews.com.