(The Center Square) - In Philadelphia, Memorial Day came to a tragic end with a mass shooting in Fairmount Park. The incident left two dead and nine injured.

Shots were heard at 10:27 p.m. as people were leaving holiday gatherings at the park. Social media videos of the incident quickly followed.

Among those injured were three children, aged 15, 16, and 17. The dead include 23-year-old Amya Devlin and 21-year-old Mikhail Bowers.

Casings at the scene revealed that there were three shooters involved. It is not yet clear whether the victims were targeted, and police are monitoring for potential retaliation.

According to Philadelphia Police Commissioner Kevin Bethel, the incident was unique due to the involvement of adults. The city has seen problems with violence breaking out amongst young people in unplanned large gatherings.

Mayor Cherelle Parker pushed back against rhetoric that dismisses shootings like this one as typical for Philadelphia.

“This is not normal, and we won’t normalize the behavior here in our city,” said Parker.

She emphasized that the city was taking a “holistic approach” to combating the problem of gun violence, one she called upon community members to take up for themselves.

Parker celebrated programs intended to build connections and provide meaningful activities that deter crime. She asked parents and caregivers to pay attention to social media accounts, which often spread the word about spontaneous crowding events.

“We can’t police our way out of this,” said Parker. “Our approach is comprehensive.”

She also noted that Philadelphia police removed 5,474 guns from the street last year and made more than 2,000 firearm arrests.

Bethel noted that at least one of the guns fired several shots in quick succession, indicating that an auto sear had been employed. The illegal device allows a magazine to be fired with just one pull of the trigger, similar to automatic weapons like machine guns.

“That is the sound of war,” said Bethel of the switch heard in videos. He noted that they are intended to hurt the most people as quickly as possible.

This weekend, Fairmount Park will host the Roots Picnic, an annual festival held by the hip hop band, The Roots. Bethel assured the press that the city would be able to provide appropriate security as it is a large-scale planned event. Officials repeated that the city would not “be held hostage” by violence like this.

Parker cited the recent parade celebrating the Philadelphia Eagles’ Super Bowl win as evidence of the city’s capacity to host large events, an important assurance with upcoming plans for the FIFA World Cup, MLB All Star Game, and America250 celebrations.