Sacramento authorities have launched an investigation after an unidentified gunman shot and killed two teens at a shopping mall on Black Friday.

Karl Chan, spokesman for the police department, said an armed man opened fire at one of the entrances of the Arden Fair Mall in Sacramento shortly after 6 p.m. The shooting killed a 19-year-old man at the scene.

Police rushed a 17-year-old boy to the hospital following the incident. He was found critically wounded at a bank outside the establishment. The victim died several hours later, the Sacramento Bee reported Sunday. 

Mall employees said they heard the gunman fire a dozen shots. Customers and workers evacuated through the corridors in the back of the mall. 

The police department said the shooting was a targeted and isolated attack. However, they refuse to disclose a possible motive for the shooting. Authorities also said the suspect is likely in his 20s. 

Chan urged people who may know the gunman or have witnessed the shooting to come forward. Homicide detectives will also review the footage from the mall’s security camera, the Associated Press reported.