The 19-year-old man arrested Monday for the shooting at a San Antonio bar that left two dead and five injured promoted his Instagram account to reporters gathered at the scene while taken into custody.

“That's me, I'm an upcoming artist,” Kiernan Christopher Williams said in handcuffs after sharing his account handle.

Williams faces two counts of capital murder for the shooting Sunday night at Ventura, a music venue and bar.

Authorities have confirmed that the two men killed by Williams were Alejandro Robles, 25, and Robert Martinez, 21. The identities of the five injured victims have not been released, but they include a 46-year-old woman and others between the ages of 16 and 19. Robles had reportedly gone to the bar with his wife to support a childhood friend who was performing at the concert.

Police believe that Williams and one of the victims knew each other and that the shooting was not random. Officials have not disclosed a motive for the incident.

“This was not a random incident and Homicide Detectives believe that at least one of the victims knew the suspect,” said a spokesman for the San Antonio Police Department.

Williams told reporters that he was acting in self-defense, claiming that someone in the bar pulled a gun on him.

“He told me he was gonna kill me,” Williams claimed. “He told me cause I bumped into him, he was gonna kill me… On the cool, I regret everything that I did. No lies. I do.”

Police said an investigation is ongoing. 

San Antonio Police Chief William McManus told reporters that authorities believe Williams was the only person to open fire.