Houston Police Department investigators said this all began when a man showed up with a gun at an apartment complex on Richmond Avenue at about 9:40 p.m.
The man allegedly threatened to kill the people inside if they didn't pay the money that was owed to him.
That's when police said one of the people inside the apartment pulled out a gun and shot the man at least seven times before he could fire first, leaving him in critical condition.
HPD said one of the bullets entered a neighboring apartment, hitting a man in the wrist.
"He (the bystander) actually tried to drive himself to the hospital and was stopped by some police officers and got some help immediately," Lt. R. Willkens with HPD said. "But he's going to be OK."
Police said the gunman cooperated with them, though it's too soon to tell if anyone will face charges.
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