Houston police said it all unfolded because the man had a gun and threatened to shoot everyone.
The shooting happened at an apartment complex on Faulkner Street near Scott Street around 10 p.m.
HPD said two residents at the apartment complex got into some sort of argument, and another resident called security.
"Security arrived to handle the incident. When they did, one of the parties in the disturbance threatened to shoot everyone out there. He walked into his apartment and came back with a handgun and pointed it at the other party he was having a disturbance with and then pointed it at the security officer," Lt. T. Riley said. "That security officer drew his weapon and fired at the suspect multiple times, striking him in the torso."
The man was taken to the hospital in critical condition, according to Riley.
Police said multiple witnesses were detained. The security guard is reportedly licensed and cooperating with the investigation.
No one else was hurt in the shooting.