Jacquis Irby, 18, killed and two other teens were injured in the shooting at Clark Street Beach in Evanston.
"The offenders and victims they had an altercation outside the entry way to the Clark Street Beach, it escalated into violence that cost the young man his life," said Evanston Police Commander Ryan Glew.
The shooters fled on foot and took off in a vehicle. Because Clark Street Beach is right next to the Northwestern campus, the university did issue a shelter in place order out of an abundance of caution, but it did not come until 30 minutes after the shots were fired.
After criticism from the community, Northwestern officials released a lengthy statement admitting the window should have been shorter, and procedures will be reviewed.
"This is a jarring situation for them to have an incident of this level of violence at what is a very typically safe area," Glew said.
Beachgoers said knowing the crime wasn't a random act of violence - police said it was targeted - gives them the confidence to come back to Clark Street beach without feeling unsafe.
But for those who have concerns, Evanston police are deploying extra resources to the beaches and parks along the lakefront throughout the weekend.
No one is in custody. The investigation is ongoing.
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