An earlier tweet from HPD said that the victims were both women. However, police later clarified and said they were a woman and a man.
Homicide investigators responded to the scene at 10223 Club Creek Drive at the Southwest Freeway service road.
The victims were found with apparent gunshot wounds behind one of the businesses at about 7 a.m.
According to authorities, the man and woman were homeless and would hang out in the area.
Witness Andrea Wallace told ABC13 at the scene that she was there at 7 a.m. with a group of people, one of whom reported seeing two people dead behind the building.
Wallace said she didn't believe what the person was saying, so she looked for herself.
"I am over there trying to save his life, not knowing that he got shot," Wallace said. "I went and pushed the lady and said, 'Get up, let's go.' She did not move. The guy, I touched him, he was all cold."
Wallace says she then called 911, and a dispatcher asked her to try CPR on the man, but it was too late.
"The individuals both appear to have sustained gunshot wounds, keeping in mind again, this is early in the investigation," said Commander K. Deese with the HPD Homicide Division.
Police searched a nearby car that Wallace says belongs to the man, who she knew well.
"He is a real nice person. He always says hi and everything, but when I seen him, it hurt me because I know him," Wallace said.
Police are now looking through surveillance video from the strip center to see if it shows the victims or any possible suspects.
For updates from the scene, follow Jeff Ehling on Facebook, Twitter and Instagram.