Investigators say it happened in a strip center parking lot in the 9600 block of Bissonnet near Plainfield.
The man's body was found around 4:30am. He has not been identified.
Police say witnesses saw a security guard shoot the man.
After the shooting, the alleged gunman took off.
The victim was taken to the hospital where he later died.
Police are still talking to witnesses but have not been able to find the security guard.
Take ABC13 with you!
Download our free apps for iPhone, iPad and Android devices